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    Gavin1977 reacted to bobfa for an article, Review | Buchardt Audio A500 Speaker System   
    Buchardt Audio A500 Speaker System
    45 days and counting...
    September 25th, 2020

    I have been on a multi-year quest for simplicity in audio systems around my home.  Recently I have mostly been listening to the Kii Three speakers with the BXT modules.  The Kii speakers are an incredible system, but they are out of most "normal budgets." I have been looking for something simpler and more in-line with personal finances.  Unexpectedly I also still have my Dutch and Dutch 8C system, and I tried the Elac Navis ARB-51 system, which falls on either side of the Buchardt A500's budget-wise.  But I am getting ahead of myself.  
    Denmark based Buchardt Audio uses a direct to consumer sales model for its equipment.  They pay the import taxes and fees.  You purchase the system, and you have 45 days to evaluate and possibly return the gear.  There is a modest return fee. For the A500, it is $50.  
    The A500 is a nicely sized self-powered bookshelf speaker from Denmark available in three finishes, White, Black, and Walnut.  The cabinet has an unusual shape that slopes backward from bottom to top.   There are three drivers; a forward-facing tweeter is in a large waveguide. There is a second 6in forward-facing driver and a third rear-facing 6in driver.  The drivers have individual 150-watt class D amplifiers.  Also, the speakers contain a multi-core DSP system that manages the crossovers and a bit more. The primary input is via a WiSA standard RF interface operating at 24bit 96kb PCM. There is a second analog input via balanced XLR. There is a USB port on the rear of the speaker for loading DSP configurations called Mastertunings.
    As I write this, there are multiple Mastertunings profiles available for download on the Buchardt Audio website. Each of these tunings changes the performance/operations of the DSP crossover. They are easy to test by installing the tuning on a USB stick and booting each speaker up with the USB stick inserted in the speaker.
    Just one more thing that the A500 provides. The DSP implements an equal-loudness contour called the Fletcher-Munson Curve (ISO 226:2003) that compensates for human hearing at lower volumes.  The Buchardt monicker is Low-Level Enhancement (LLE).
    The second part of the system is the Hansong Stereo Hub that Buchardt sells along with the speakers. The Hub is an optional purchase, but it is a primary tool for using the speakers.  The stereo hub is the WiSA transmitter and provides multiple inputs along with Wi-Fi streaming.  It comes with a nice wireless remote for controlling volume, input selection, and more.  
    The stereo hub has some smart tricks up its sleeve.  
    - It is a Chromecast and Airplay receiver and has Spotify Connect.  
    - There is also Bluetooth and UPnP.   
    - There are multiple physical inputs, Line, three optical, one digital, USB, 3.5mm, and HDMI ARC.
    There is one other feature; Room Correction, for frequencies below 300hz. Using an iPhone app to sweep the room with the speakers emitting an audio pattern, the software calculates the needed adjustments.  It sends the info to the Hansong Stereo Hub for operation.
    The above is a short intro video we shot for The Three Techs!
    September 30th, 2020
    I have the speakers connected to AC power using Puritan Audio Laboratories power cables and the PSM-156 Mains Purifier.  An HDPLEX-200 LPS powers the Stereo Hub.  
    The speakers are on Elac single post filled stands using Isoacoustics Gaia-1 isolators.  The speakers do not have mounting inserts, so I use Sound Anchor Blue Dots to hold them on the speaker stands safely.
    NOTE: I already had the ancillary devices listed above available for use on the system.  While they are "upgrades" and optional, they add significant value!
    My everyday listening tool has been my Ryzen 7300 based Roon Server.  With the Hansong Stereo Hub, I have many other options.  The Hansong hub and the AURALiC Altair G1 are both Roon endpoints.  The Hub only through Google Cast. 
    I am also listening with Spotify Connect, Tidal app, Qobuz app, Audirvana, SoundCloud, Bandcamp, etc.
    I have played with MConnect, Bubble UPnP, and a couple more control point apps on iOS and Android.  I am going to leave this for later.  There is just too much to do.
    According to Buchardt Audio, the speakers need around 100 hours to break-in.  I found that after about 20 hours or so, things started to relax a lot!  The "piston-rings" seem to have gotten their Groove-On!  As time goes on they continue to improve.  
    October 3rd, 2020
    Room Correction and listening paths
    In my room, there is a 30-40Hz bump at about 5db. There are also a couple of dips above that. I have a lot of carpet, fabric, and the room's rear is mostly open to the home's entryway.  No listening room is perfect!  In this case, the Living Room has to function as a Listening Room, and I really cannot embellish it with acoustic add-ons.  Some DSP software helps things out.

    I have two paths to the speakers that I want to outline.  The first path is the Buchardt supplied WISA Hub.  I do not know precisely where the magic is in the WISA system, but I have not heard anything in its price range that comes close to the sound quality I am getting.  The flexibility that the Hub provides to this system is an almost perfect intersection of services for streaming music playback.  I also connected my Rega Planar 8 turntable and pre-amp to the line-in.  What more could I ask of the Hub?  At least one more thing, I can tell Google Assistant to play music on it!  
    The second path for my music is through my AURALiC Altair G1 directly to the A500 speakers via their balanced analog inputs.
    There are a couple of advantages to the G1, from the lovely display on the front of the device to the Lightning DS application that ties everything together, high-res Local Music, Tidal, Qobuz, Internet Radio.  
    So, the G1 and the Hansong Stereo Hub pair give me access to virtually every streaming and local music source I can think of.  I get to play with Room Correction, listen to LP's, talk to my stereo; WOW!
    I have been putting off writing about the sound for a long time now.  It takes quite a while to accumulate hours on speakers located in the core of the home during the ordinary course of family life!  
    The other part of the problem is what audio path do I evaluate?  I really do not want to decide what the "best test path is."
    I am trying to promote the use of the system, so I have been testing multiple approaches.  While Sound Quality is essential in our home, the simplicity of operation may override sometimes. Having the Virtual assistant play something on demand is very compelling. Does Apple Music over Airplay sound better than Spotify Connect? Do I really care? I am not sure.
    During this process, I have found many hiccoughs in multiple systems, software and hardware. I may note them in a separate thread here on Audiophile Style to not confuse this report.
    The Primary Paths that I have chosen are as follows:
    I am streaming via Google-Cast and Apple AirPlay from apps on my iOS and Android devices. 
    Altair G1 via Analog XLR, the A500 Speakers using the Lightning DS app on iPad.

    The other issue here is the data path.  Using all of these services and streaming protocols, I do not always know what the sampling is.   Some of the testings are about functionality and not Sound Quality.
    Did I cover my tracks well enough here?  Or is the light at the end of the tunnel a Freight Train headed my way?
    October 10th, 2020  
    Short-cut to a sound quality test? I am not sure.

    I used the Hub and the G1 as two Roon Zones in my testing, comparing the WiSA path vs. the Analog XLR path into the A500 speakers.  
    For a few days, I used both sighted and blind to expose the difference between the two paths.  The Altair G1 has a better presentation than the Hansong Hub. The G1 has a tighter presence and more clarity. The overall feeling of the music with the G1 is striking. I have had two friends visits, masks on windows open.  Both were really surprised by the A500's.  One vote for G1 being a lot better.  The other was an abstain as we did not have enough time. For me the Buchardt A500 is the clear winner here.   I can enhance them with my Altair G1 and that has been three steps forward for me.   
    NOTE: I conducted the same test with the ELAC Discovery Connect and the Altair G1.  The Discovery Connect and its wireless protocol have pronounced performance degradation to the ELAC NAVIS ARB-51 Speakers I was testing last month.   It was not an acceptable solution for me.  The Elac's have been returned.
    I told you that this was hard!  Simplifying my system design has gotten more complicated to evaluate than expected.

    The A500's stated frequency specifications are 25hz to 40,000khz +-1.5db. I will not pretend to be able to measure this or hear it for that matter.  I can talk about what I hear, and that has been full of surprise and delight. 
    Out of the box, the A500's did something new for me.  The treble did not sound harsh.  The bass response was jaw-dropping.  How did the Buchardt Audio team make this happen?  As I have been auditioning them, I have not once felt something was off.  I am repeatedly amazed at the depth and breadth of the sound stage. Vocal and small ensemble performances feel almost alive.  The A500 speakers have exceeded my expectations in several areas, apparent sound stage, bass response, and WiSA sound quality.  They have responded well to the sound quality enhancements I have used, and their system flexibility fits right in with my desire to play with things.
    In communicating with Mads Buchardt, who seems to answer everyone's email, he suggested a couple of things from my initial setup.  He indicated that I should keep them further apart because of the way that the tweeter waveguides work.  He also outlined the procedure for measuring the room with my iPhone, as they have not done a video yet! 
    Oh, back to my listening report.  
    I consistently find vocals to be very pleasing with these speakers.  A couple, in particular, are Dominique Fils-Aimé and the lead singer from Blues company.  It has been wonderful to sample Annie Lennox across the years.  In Eva Cassidy's Live at Blues Alley I can hear more of the human sounds in the recordings, breathing, mic distance changes, etc. They seem more present.
    I enjoy piano music.  Getting a piano recorded well, and playing that back in a home environment is challenging.  I have found that many piano recordings sound harsh or odd to me. Many times the faults were with my reproduction equipment! With the A500's the number of recordings that exhibit that problem seems to be shrinking one by one as I listen to them.  I have a lot of listening to go before I get to zero, and there is always the internet with more!
    In my discussions with Mads Buchardt, he suggested I try the "new default master tuning." You have to format a USB stick and put the master tuning file on it.  Then power down the A500 speaker, insert the USB stick, and power it up.  The LED's will do a little circle dance to indicate success.  You have to do this for each speaker.
    I have only played a little bit to see if it worked.  I re-loaded the original MasterTuning so that I could finish these listening tests without any change.  Time is running short.
     21 Days in -- Small changes-- October 15th, 2020
    I have decided to keep both of my streamers in the system.  I am using the Hansong Hub to do the "casting stuff" and have the analog input for my turntable.  When there are some software updates, I will look into other uses.  
    I have proven to myself that the Hansong Hub and WiSA streaming sounds excellent and provides a lot of functionality I want.

    Streaming Week -- Friday, October 16th, 2020
    Things are progressing rather well here.
    This feels like Cake Week on The Great British Baking Show.  So many flavors to taste! I have been listening to Apple Music.  The User Interface of Apple Music is excellent.  Playing back Apple's streams of AAC  audio is a pleasure on the A500's.  It is a great way to discover music.  Apple has an extensive selection of music, and its curated playlists are great.   I am also trialing Spotify Premium to test Spotify Connect and understand their systems better.  
    On the Altair G1, I have my local music with Tidal and Qobuz.  I have been playing a lot streaming from both Tidal and Qobuz.  
    At some point I have to make up my mind and pick ONE streaming service.  Simplifying is not just the hardware side of things!
    October 24th, 2020  -- 30 days and counting
    The Battles on Stage — 8c vs. A500
    It has been a month! I have done too much work to get here.  Messing about with different streaming systems, control point apps, speaker stands, and locations, WHEW!   
     I have settled into a routine of just listening to the system when I want no heavy planned sessions.  The only requirement I am still observing is to make sure I listen through both the Altair G1 and the Hansong Hub in the same session. Nothing fancy, just keeping both in mind.
    I am still finding the soundstage's overall presentation to be one of the outstanding features of the A500's.   As I noted before, vocals stand out on these speakers.  Singers like Eva Cassidy are some of my favorites.
    I have also completed a SHORT comparison of the Buchardt A500's to the Dutch and Dutch 8C speakers this weekend. I am using the Analog XLR interface from the Altair G1 for my listening. The differences are smaller than the similarities. Diminishing returns?  Both systems have lovely imaging; they both have extended bass range.  8c's sonic presentation has more midrange detail, and they have a lot of weight.  They are a bit more forward. The 8c's let you know that they are in the room both physically and sonically.  I realized that I had been using a loaner set of XLR cables in the system before this test, and that has changed the Analog character of things. That will be remedied shortly when my AudioQuest Water cables arrive.
    As I mentioned early in this process, this is not a fair comparison.  The  8c's are around triple the price of the A500's.  This review is not about the Dutch and Dutch speakers, but they influence my thinking, as do the Kii Threes!  
    Finally, I have been put in contact with the engineering team at Hansong.  I have sent them the list of issues I have found so far.  They have helped me with a couple of cases where I was doing the wrong thing.
    October 28th, 2020
    My Playlist
    I took some time today to start building a playlist to highlight some of the music I have been listening to during my trial.  You will find the Qobuz playlist down at the bottom of the article.  I am also linking to a couple of other playlists that have been fun!
    Kii Audio Spring 2019 — Updated
    Audio Consultants Playlist

    And the icing on the cake: We also figured out one of my problems—the A500's need a bit higher volume from the Altair G1 to wake up from sleep.  I thought I had a problem.  It was user error.
    November 9th, 2020
    This is the last day of my trial.  Let me level set my decision here.  I am comparing the A500's and the Hansong Hub against the Dutch and Dutch 8C and the Kii Three with BXT.  Being able to directly compare these three systems is a very unique opportunity.
    The A500 has a split personality.  The first is their analog side.  The audiophile in me almost giggles to see that.  I can hook just about anything up to that input.  It allows me to dig in and play around.  The second side is the Hub.  This little Swiss Army Knife has so many possibilities for digital, wireless, and analog my head spins.  So I am a kid on a merry-go-round, dizzy and laughing!
    I am fascinated by the Hub. I mostly use it for AirPlay, background listening, research, discovery, etc..  I am also playing with Spotify Connect to see if I can tell the difference between it and Apple Music.
    In my testing, I have exposed several software issues with the Hub, mostly with Google Cast.  All of my problems have been reported.  Since I mainly use AirPlay and Spotify Connect, this has not been a significant issue for me. 
    I am looking forward to proper Roon Certification although I have mostly abandoned Roon due to multiple interactions issues and reduced sound quality.
    As noted above, the Altair G1 is my Server/Streamer/DAC to feed Balanced XLR analog to various systems.  

    So, Bob, are you keeping them???   The answer is YES!  
    I have never experienced a pair of speakers that present this level of musical reproduction experience at this price point.  The A500’s show you when you have all of the pieces linked up to produce amazing sound in your own living room. When something is not right they show it to you.  When something soars to great heights, the shine a light on it.  These are truly what I consider “Performance Listening” speakers.   Mads Buchardt should be very pleased to put his name on these speakers.  The teams that built them should be celebrated.

    There is more to be done!
    I really want to see some software updates for the Hansong Hub.  I want to try different mastertunings.  I would like to see Roon Ready on both the 8Cs and the A500 hub.  I am breaking in my AudioQuest Water cables, and  I am waiting for some Herbies Audio Labs, Cone/Spike Decoupling Gliders.  I want to see if I can use them in place of the Gaia-1’s
    I hope that this journey through my evaluation has been enjoyable and encourages others to try out other system components.

    Thanks to Mads Buchardt for spending so much time responding to my emails and connecting me to the right folks directly for reporting my issues.  His support has been very encouraging.
    So "Enjoy the Music"
    ** I am closing this report here to satisfy my goal of getting this review done in the allotted time.  There is another chapter going on as I type this.  Keep a watch on Audiophile Style for more.  We will also do another video when I am “Finally Done”

    Product Information:
    Buchardt Audio A500 Speakers — Walnut W/ Hansong Hub.    4,350.00 Euros (LINK) User Manual (13MB PDF) (LINK) Stereo Hub Quick Start Guide (6MB PDF) (LINK)  
    AURALiC Altair G1
    Melco N1-ZH60 
    IsoACOUSTICS Mini-Pucks for the Altair G1 and Melco
    Rega Planar 8 Turntable with Ania cartridge
    Musical Fidelity MZ-VYNL phono stage
    Audioquest Evergreen RCA cables for Phono to Hub
    Mogami Gold XLR Cables
    AudioQuest Water XLR cables
    Elac Single post stands.
    Sound Anchor Blue Dots to stick the speakers to the stands 
    IsoACOUSTICS Gaia 1 isolators
    IKEA Cutting boards as platforms
    Puritan Audio Laboratories 
    PSM-156 Power Line Filter
    PAL power cords as needed to equipment 
    Apple iPad Pro 12.9 (first generation) as a control point
    DIY RYZEN 7300 based Roon Server 
    2014 Mac Mini for Audirvana
    Pixel 3a control point
    iPhone 11Pro MAX Camera and control point
    Other Items
    Dutch and Dutch 8C speakers
     on Sound Anchor adjustable stands
    Kii Three+BXT Speaker System
     With speakers spread all over the living space for the last six months, it is great to have a very patient spouse! 
  2. Upvote
    Gavin1977 reacted to ray-dude for an article, Reality Quest: Going to Extremes with the Taiko Audio SGM Extreme (Part 5 of 5)   
    Part 1 - Introduction and Digital Audio Optimization Foundations (Link) Part 2 - Enter the Extreme (Link) Part 3 - First Impressions and Basic Configuration (Link) Part 4 - Tweaking Up the Extreme (Link) Part 5 - Extended Listening Impressions, Learnings, and Conclusions  
    So enough A/B testing and back-breaking lifting and moving. Time for some extended listening with the Taiko Audio SGM Extreme! (for details on each track and what I listen for for each, please see the end of Part 1 of this review)

    Extended Listening Impressions

    When I finally settled in for some extended listening with all the tweaks and optimizations in place, I was struck again and again by how real and present everything sounded. It really was a kid in the musical candy store experience, and such a delight to get connected again and in a new way to so many remarkable musical performances.
    On Noche Maravillosa (Begona Olavide), I was struck by the tangibility and presence of the percussion. Each instrument and player is remarkably distinct, but the overall performance comes together into a wonderfully coherent whole. There was a subtlety and layer of expression in some of the performances that I had never heard before (caught me short actually...I’ve heard this track many hundreds of times), with a sound stage that easily extends well through 180 degrees. Todd Garfinkle of MA Recordings is both a remarkable musician and recording engineer, but hearing his work in this way really gave me a new appreciation of how he blends both perspectives into his recordings.
    That same remarkable nuance extended to the vocals on Voglio De Vita Uscir (La Chimera). Even more, I was struck by the coherence of the performance (it is rare for me to hear this level of coherence outside of a live performance). The sense that the musicians are listening and reacting to (and creating with) each other is tight and palpable. Control and dynamics are off the charts, but absolutely controlled and relaxed. The combination of incredible dynamics with absolute control is striking, and the hallmark of the Extreme sound.
    Fischer’s Mahler #2 is an incredible recording and performance, riding a roller coaster of emotions and dynamics with the master at the helm. With the Extreme, I get a wonderful sense of the mastery that Fischer demonstrates with the Budapest Festival Orchestra. The canvas of sound is vast, but at the same time subtle and dynamic. The overlay of themes and musical lines is magnificent. Hearing the incredible nuanced artistry in a performance of this caliber through the Taiko Audio SGM Extreme + Chord DAVE + Voxativ 9.87s is truly remarkable. Even in the most aggressive moments (of which there are many), control remains absolute, and nuance and subtlety of the individual musical lines and performances still shine through. 
    Going back and revisiting Reiner’s Scheherazade, but now in a fully optimized configuration, what I’m hearing is absolutely glorious. This is a time machine back to 1960 Chicago. A magical performance for the ages. What an incredible experience. Truly, hearing a performance like this makes all the effort and investment in building an audio system worthwhile, just to bring such incredible artistry to life once more.
    My reaction to Fischer and Reiner was a bit emotionally overwhelming. In general, I have a bias for smaller ensembles and more intimate musical performances where I am connecting with the individual performers, but with the Extreme, the full force of large scale orchestras sits in perfect harmony with the individual grace and humanity of the individual players, and indeed brings them together into something much larger still. I get the feeling that with the Extreme, there may be a lot more listening-time spent with these large orchestral works in my future.
    Choral works like Hodie Christus Natus Est (Dunedin Consort) are extraordinary. The sublime performances and harmonies are really something to experience at this level. The speed and dynamics of the Extreme really brings out the nuanced intonations of the vocalists, and the remarkable sense of space and spatial resolution brings the chorus together in a way that gives me even more admiration for a performance of this caliber.
    On the magnificent Arnesen Magnificat (TrondheimSolistene), it really all comes together: the choir, the orchestra, the organ, the sweeping cathedral where the performance took place. In this recording, I’ve always felt that the cathedral should have been credited as a performer on this album - the sense of space and music reverberating within it is so remarkably engaging and encompassing. With Extreme in my system, the hologram is even more tangible still. Absolutely glorious!
    Moving back to small scale recordings with the Bassface Swing Trio, the speed and dynamics of the Extreme really bring out the best of all three performers: the sense of tangibility and nuance of the bass line, the attack and physicality of the drums, and sense of being with a real piano, where every note dances with every other note and across the soundboard. All this with performers who are absolutely tight and dialed in. Just delightful.
    Revisiting the gift that is Shamus-Ud-Doha Cader-Ud-Doja (and the remarkable Ustad Nusrat Fateh Ali Khan), the master has me in literal tears from his opening call. With all that is going on in the world, I can’t separate how much of this overwhelming emotional reaction is because of what I’m hearing vs how much I am in need of hearing it, but I am enormously grateful for this salve for the soul.
    After a brief break to recover, back to some more intimate recordings. Rob Wasserman’s bass on Stardust (from the “Duets” album, with Aaron Neville) has never felt so deep and so resonant and so present. The full soundboard is tangible, and the complement to Aaron Neville’s full body singing style is a lovely pairing. Each singer and Wasserman’s bass is a real tangible physical presence, and the artistry is truly off the charts.
    On Alison Krauss’ live rendition of Let Me Touch You For A While, the masterful level of musicianship of Union Station really shines with the Extreme, with each player complementing each other beautifully, and the nuance and presence of each instrument blending in a way where the whole is much greater than the sum of the parts.
    Eva Cassidy’s Fields of Gold (from “Nightbirds”) has always had a recording that fell short of the (remarkable) performance for me. The stresses and strains of recording equipment being pushed beyond where they should have been always has me on edge waiting for a break. The speed and dynamics of the Extreme greatly diminish my wincing at the more saturated parts of the recording, but I still get a slight flinch at times. Overall though, a much more inviting and engaging experience than I’m used to, which for this performance, is a gift worth appreciating.
    Turning my attention to some favorite piano recordings, for me that means revisiting some favorites in the Blue Coast library of recordings. Cookie Marceno (master of the house at Blue Coast) has a lovely and lovingly mic’ed vintage Steinway in her studio. When I hear her recordings, the character of that piano is unmistakable, and I am always reminded of the sounds etched into my heart and soul of my daughters playing our vintage Steinway as they were growing up. With Extreme, that “whole piano” experience that I so appreciate in real life is there in Cookie’s recordings in all its glory - all the strings and soundboard and room coming together for an experience that I know all too well and miss all too much. In particular, Sareena Overwater’s One World has a vividness and realness that takes a breathtakingly beautiful and relevant performance and elevates it to an anthem.
    Moving to guitar and voice, that “whole piano” feeling becomes a “whole guitar” feeling, with the strings and fretboard and soundboard all present and tangible. The speed and controlled dynamics of the Extreme shine a particularly compelling light on stringed instruments. Meghan Andrew’s 99 hits even harder for this soon to be empty nester, and then listening to Willie Nelson’s Vous et Moi (from “Night and Day”) reminds me even more that the best is yet to come. On Vous et Moi the sense of friendship and mutual respect and flat out joy of the performers is so intoxicating and full of grace. The Extreme makes that studio real again, and I’ve pulled up a stool to sit with the band.
    On Arianna Savall’s exquisite L’Amour (from “Bella Terra”) all the nuance and beauty of the remarkable resonance between Arianna’s harp and her voice is absolutely breathtaking. As she harmonizes with her harp, the harp responds and sings with her. The layers and interplay and exquisite dance between voice and instrument are taken to a new level with Extreme.
    Shifting to some favorite binaural recordings, I was very excited to hear what the Extreme can really do. I have found that when my system is dialed in just right, the best binaural recordings become true 360 holographic surround (all around?) sound experiences. Alas, it takes vanishingly little to have that all around-you and above-you sound stage and collapse it. 
    Listening to Melissa Menago’s Traveler (from “Little Crimes”) I’m in David Chesky’s favorite Brooklyn church, and it is raining outside. The rain accentuates the sense of space, and it is all just right and blissful (wonderful). Airplane (from the same album) has wonderful articulation of vocals and instruments. Speed and dynamics are awesome, as is naturalness and realness of the performances. 
    Amber Rubarth’s “Sessions from the 17th Ward” shows that the same naturalness and realness is still there even with more complex binaural performances. The strings on Don’t You reach right out, command your attention, and draw you closer in a way that live violin always does, but recorded violin rarely does (Amber’s voice does as well). 
    Carla Lother’s Ephemera (from “Ephemera”) is a remarkable interpretation of a remarkable poem by William Butler Yeats. It is also a near perfect recording that is remarkably delicate on playback. Over the years, I’ve looked to this incredible song (and poem) for inspiration, but also to shine a bright light on how my system could be keeping it from being fully realized. Listening with the Extreme, the remarkable speed and dynamics of the Extreme render Ephemera the finest I’ve ever heard - clear, vivid, real, engaging, and engrossing.
    Turning up the volume, it was time for some Daft Punk (Get Lucky, from “Random Access Memories”). Fantastic album, and I adore the care and passion that went into the performances and capturing the performances. As you would expect, the Extreme really brings the speed and dynamics here, but I’m even more impressed with how transparent and natural things sound (no bloat, no overshoot, no sense of sloppiness at all).
    Closing out with some favorite jazz performances, Dave Brubeck’s Take Five (from “Time Out”) again surprises with the combination of naturalness and speed and transparency. I get the sense that I could listen for days, which has always been difficult for me on this recording. 
    As always, I closed out my listening session with Mile Davis So What (from “Kind of Blue”). As I mention in my tracklist way back in Part 1 (LINK), I consider this one of the finest recordings and performances of the 20th century. Until there is a time machine to take me back to March 2 and April 22 1959, I will buy every new remaster of this album, and play it on every piece of high end audio kit I can find.
    With the Extreme, the masterful grace of Bill Evans is completely out of this world. Cobb’s percussion line is the finest I’ve ever heard it. Coltrane absolutely erupts into the room, and I know who I’m going to be listening to for the next several hours...wow! Hearing performances like this in this way makes all the system optimizing and tweaking work so worth it.

    So What Is Happening Here?

    Reviewing my notes, what comes through again and again is “speed”, “control”, “dynamics”, “transparency”, “naturalness”, “wow”. The Extreme is delivering remarkable performance by being remarkably performant, but also by being capable of so much more performance than what is needed that it can maintain remarkable control. 
    While the name certainly brings a smile when you take a look at what the Extreme brings to the table, “Extreme” is also the perfect representation of the design philosophy behind every single component, design decision, and execution element of the Extreme. Everything is over specified and over allocated and over built not as a flex, but as part of a very purposeful design to have dynamic loads on the system during music playback perturb core components as little as possible. Have the best possible, most powerful and fastest components you can possibly have, and use them as little as possible.
    Does one need 40 logical Xeon cores and 48GB of hand selected custom memory and 700,000uF(!) of ultra premium capacitors with a 10gbps USB channel in a 100 pounds of precision milled aluminum and copper and panzerholz case to stream 44/16 Redbook files to a DAC? Of course not. 
    However, having that type of capacity available means that processing loads and heat loads and power loads can be spread and isolated as much as possible, and that the act of music playback registers as little change as possible on the system. The result is sound quality with speed and precision and transparency and dynamics and naturalness and control that are way beyond anything I’ve ever heard.
    Vocal intonations have a level of subtlety and physicality that is simply stunning. That sense of music coming from the head and throat and chest is tangible, and the emotional connection is vivid and real. The speed and control on string plucks is striking. Like the physicality of vocals, there is a tangibility of the soundboard on the stringed instruments that I’ve only experienced in front of real instruments. More than just imaging, the coherence of sound coming from the performer and the instruments is letting my brain perceive the performance as real and reconstruct the scene, with striking speed and physicality and realness.
    With the Extreme, everything is better, but I did note a surprise outsized benefit to marginal or dynamic-range-compressed recordings. It was as if the speed of the Extreme was able to increase the perceived dynamic range of these compromised recordings, and certainly make them more enjoyable and listenable.
    Perhaps the most interesting and compelling part of listening to music with the Extreme is that the remarkable dynamics and speed don’t overwhelm and over drive the music. The incredible speed and dynamics is balanced by every more remarkable effortless and complete control. The combination of speed, dynamics, and effortless control reveals a level of nuance and subtlety in recordings and performances that I simply have never heard before. For the best performances, there is a whole new amazing layer of artistry that has always been there, but that has somehow always been held back or washed out by other systems I have owned.

    Bringing It All Together

    Reviewing my experience with the Extreme, the best I was able to do to improve things was to give it better inputs (network and power), and better outputs (USB), and a better place to hang out (vibration isolation). Everything else is already tuned and optimized way beyond anything I could do for myself. Below is a final snapshot of my new optimized reference system:

    Although the diagram is seemingly complex, when you boil it down I am going fiber internet from the street to ONT to EdgeRouter to opticalModule to Extreme to USB to Chord DAVE to speaker cables to Voxativ 9.87’s. This is the simplest and most transparent system I can imagine, leaning heavily into the design and engineering genius of Emile Bok (digital servers), Rob Watts (digital to analog converters), and Holger Adler (analog transducers).
    As an added bonus, after literally years of digital audio experiment after digital audio experiment being strewn all around (and over and under) the living room, here is how my listening setup looks today:

    Yes, for all the lost and forlorn civilians out there waiting for their audiophiles to come back from the depths of madness, there is hope at the end of the Extreme rainbow (at least until the tweaking gene kicks in and it all starts over again...maybe it’s time for an ultra short throw projector and a 10’ screen? 

    So Where To Go From Here?

    So where to go from here? Other than hitting the gym so it isn’t so painful to move the Extreme next time, my spidey-sense is that there is still goodness to be found in the USB implementation in the Extreme, maybe a bit more to be squeezed out on the network side, and I am always hopeful that there is more to be found by upgrading the power supply.
    The ASMedia USB 3.1 gen 2 controller in the Extreme has phenomenal performance, but there is a new wave of USB controllers coming (including from ASMedia). In addition, the ASMedia controller in the Extreme is clocked and powered by the ASUS motherboard. An add-on USB card like the JCAT USB XE (with external power and high quality clocks) could give a lift above what the brute force ASM controller can deliver. I look forward to being able to audition these kinds of cards in the future.
    Similarly, there are many audiophile network cards available on the market, and exciting reports about the impact of a new generation of audiophile switches. There may be opportunities to tweak up performance even higher, but sound quality of local content vs streamed content on my system is so danger close, I may be at the point of diminishing returns (at least until AT&T gives me a key to the fiber concentrator up the road, and I can convince Sean Jacobs to build a carrier-class LPS for me.
    Lastly, for the Extreme power supply, I mentioned in Part 2 (LINK) that I believe that much of the secret sauce of the Extreme starts and ends with the remarkable extravagance of the Extreme power supply. I have yet to hear any piece of digital audio equipment that did not improve with better power, and I have to believe that there is more goodness to be found with the Extreme, but what direction could that take?
    With that level of investment in filtering capacitors in the Extreme, there may be an opportunity to push for even bigger and faster and more dynamic power sources, and be able to elevate system-wide performance higher still. My hope is that the extravagant filter bank may be able to support even more “extreme” brute force in the power supply, making even faster power available while not losing that remarkable control that the Extreme excels at. Alas, there is nothing for us DIYers and tweakers to do here, except trust that if there is more sound quality to be found via the power dimension, Emile will find it, and he will find a way to get it to all of us.

    So Is It Worth it?

    So, after ~26,000 words, the $26,000 question: Is it worth it? 
    Weighing in at 100 pounds, the price of the Extreme is roughly equivalent to what you pay for 100 pounds of silver or 1 pound of gold. This is rarified air for even the most audiophile obsessed among us.
    Having now been able to spend several weeks with the beast, the Extreme is a marvelous achievement, and a stunning embodiment of the design philosophy and expertise of Emile Bok. It is quite simply the finest digital server I’ve ever heard (by a LOT). In a hobby where there is never consensus about anything, the universality of the opinion amongst those that have heard the Extreme speaks volumes. The Extreme is a seminal product, and one whose influence will be seen in other commercial offerings and DIY builds for years to come.
    So yes, one would expect that a $26,000 server will sound good.  The capital Q Question is “Is it worth it?” 
    As with all such questions, worth is in the ear (and wallet) of the listener. For me, as I have traveled into the digital server rabbit hole, the Extreme has taken anything I could have tried or would have wanted to try to many many levels beyond what I’d ever even be able to try (a 700,000µF Mundorf and Dueland capacitor bank?!? Are you kidding me?!?!?). 
    But does it make sense to push things to these extremes? Can one get 99% of the value at 20% of the cost, or even 5% of the cost? 
    There are many quality and respected digital audio server options that fill the (considerable) gap between my current optimized NUC setup and something as extravagant (and expensive) as the Extreme. Where do they fall on the price/performance curve? Is there more value to be had with the fine solutions from companies like Innuos and Pink Faun and Aurender and the many others that are delivering very capable digital audio solutions these days? Or even some of the more advanced DIY builds like are being shared in the outstanding Building a DIY Music Server thread and elsewhere? 
    Alas, I do not have ready access to these systems to do a proper side by side comparison to be able to answer that question (and Alas2 Pandemic-induced restrictions make it even more difficult to cajole folks to bring their systems over for side by side listening). As others are able to hear and compare the Extreme with other fine server options out there, I look forward to reading their reports.
    For me, as I was looking at what could have been another 3 or 4 iterations of builds and upgrade cycles to get to an end game optimized server, I did the math (materials, power supplies, master clocks, case work, time, frustration, rework, messes, disruptions, etc.) and got within spitting distance of the cost of the Extreme, so the math worked out for me (it was an easy call actually). Moreover, Emile is an absolute delight of a person to be working with, and I'm very pleased to support the work he and his team are doing, and to benefit so greatly from it.
    Is it the right decision for everyone? Absolutely not. Aside from the heavy cost of entry, there is a lot of satisfaction to be found in DIY builds, and the opportunity to make targeted investments in components that matter the most for you. 
    However, if your budget can tolerate it and you want to jump to the ultimate best solution and skip all these intermediate steps, the Extreme delivers on everything it promises and much much more. It brings the relaxed welcoming sensation of listening to the finest analog setups, with the precision/speed/detail and dynamics/noise floor of the finest digital setups. Performance is at such a stunning level that you can clearly hear when processes are running and not running on a 40 core 48GB Xeon monster. For all the incredible power and speed and dynamics the Extreme delivers, there is a level of control and naturalness and grace which is greater still. The result is being able to hear (and feel) nuances and artistic subtlety in performances that I’ve never heard before.
    I’m sure someone can and will do better at some point (that fact that seemingly small changes in network and power are so audible confirms that), but if your pocket and back muscles can take it, the Extreme is a true reference against which all other digital front ends should be measured.

    Acknowledgements and Thanks
    My sincere thanks to all those in the audiophile community that have blazed the way for digital server optimization (most of that trailblazing happening right here at Audiophile Style). Your work and generous sharing of experiences is incredibly appreciated. My special thanks to those that contributed insights and feedback on this novella of a review, and to all of you who braved this week long Extreme Week odyssey!
    As an addendum, in another thread this week the very legitimate question was raised about the wisdom of something like Extreme Week with all that is going on in the world. (I hope the OP forgives me for repurposing some of that discussion here)  
    While this journey started for me before most of our worlds turned upside down, was it still one worth pursuing and sharing now that all our worlds were decidedly upside down?
    I did reflect a lot on this over the last couple months, and struggled with it. During a very difficult time, music (and a new way to enjoy music) has been a very welcome and meaningful part of my life, and an affirming and hopeful balance against the many serious things that are happening all around us. 
    Alas, there is never a good way to deal with what no one should ever have to deal with. In a world of no good choices, I often return to a favorite poem from Mary Oliver (reproduced below) and remind myself "Joy is not made to be a crumb". Remembering to feel joy, to feel the vast canvas of emotions at the core of the music we all love and enjoy, has been a cherished candle for me in a time of great darkness.
    Peace and health and joy to all of you in a very difficult time, and my thanks to Chris for hosting this community and this conversation, and for giving space for that candle to shine.

    If you suddenly and unexpectedly feel joy, don’t hesitate.
    Give in to it.
    There are plenty of lives and whole towns destroyed or about to be.
    We are not wise, and not very often kind.
    And much can never be redeemed.
    Still, life has some possibility left.
    Perhaps this is its way of fighting back, that sometimes something happens better than all the riches or power in the world.
    It could be anything, but very likely you notice it in the instant when love begins.
    Anyway, that’s often the case.
    Anyway, whatever it is, don’t be afraid of its plenty.
    Joy is not made to be a crumb.
    ~ Mary Oliver
    Community Star Ratings and Reviews
    I encourage those who have experience with the Taiko Audio SGM Extreme to leave a star rating and quick review on our new Polestar platform.
  3. Upvote
    Gavin1977 reacted to ray-dude for an article, Reality Quest: Going to Extremes with the Taiko Audio SGM Extreme (Part 4 of 5)   
    Part 1 - Introduction and Digital Audio Optimization Foundations (Link) Part 2 - Enter the Extreme (Link) Part 3 - First Impressions and Basic Configuration (Link) Part 4 - Tweaking Up the Extreme Part 5 - Extended Listening Impressions, Learnings, and Conclusions (Link)  
    In the first three parts of this review of the Taiko Audio SGM Extreme (linked above), I looked at the Extreme out of the box, and the remarkable performance it is capable of. In this Part 4 of my review, my focus shifts to if and how to make the Extreme better by tweaking factors outside the Extreme itself (networking, power, etc).

    So Can We Get the Extreme from Ridiculous Speed to Ludicrous Speed to Plaid?

    Emile has often said that the only attention you need to give your Extreme is good power, good network, and good mechanical isolation.
    Taiko recommends that the Extreme be on an electrical circuit that can draw 2kW of power (in the US, this would mean the Extreme has a dedicated 15A or preferably 20A circuit that it is not sharing with other devices), with good quality outlets (rhodium, silver, or gold connectors) with a high quality power cord. Although the Extreme itself only requires a small to modest amount of power when running (as little as 60W), it greatly benefits from copious amounts of transient current (the faster the wall can respond to current demands from the Extreme, the better Extreme can deliver and regulate power to its internal systems). It will work great on a standard 15A shared circuit (that’s how I was running it out of the box), but it just does better if there is more transient power available to it when it wants it. Lastly, Taiko also recommends  not having any powerline networking polluting your electrical system with added noise. 
    For networking, Taiko recommends a low RFI network connection (impact will vary based on your local setup and circumstances). The Extreme comes with a StarTech optical network card, and Taiko recommends that those looking for the ultimate performance explore whether an optical network connection works better than copper ethernet for them.
    Lastly, the Extreme is a beast, and requires a stable platform. Taiko recommends that it be on a stable shelf or platform as close to the floor as possible to minimize adverse impacts from mechanical vibrations.
    So if we assume that cpu/motherboard/memory, storage, internal power, clock, and OS/software have already been optimized to the Nth degree and can’t be improved on, my next step was to assess the impact of optimizations of:
    Power - Assuming the internal power supply can’t be easily improved upon, how much lift is to be had moving to a dedicated 30A circuit, isolation transformer, and with a premium power cord? Network - What optical network topology is optimal for streaming, and what kind of lift over stock copper ethernet? USB - How do different USB cables impact sound quality? Mechanical - How does sound improve as mechanical isolation improves?  
    For these tests, I stepped up the tweak ladder one OCD step at a time, then pulled it all together when I moved my Extreme to its final permanent home.

    Power Optimizations

    As a reminder, my tests so far of the Extreme have been with a generic power cord plugged into a generic power strip (with all my other AV equipment and various SMPS plugged into it) which was in turn plugged into a generic outlet on a shared 15A circuit behind my media console. 
    The performance of the Extreme with this level of (lack of) attention to power hygiene is remarkable, and a testament to the quality of the design of the Extreme power network and casing. That being said, can we make it better by providing the Extreme better cleaner power and more power?
    Starting at the electrical panel, I evaluated the following upgrades:
    A dedicated 30A circuit (10-2 Romex) connected to an upgraded high conductivity outlet, dedicated only to the Extreme. The line length from my electrical panel to this outlet is ~15', so it is in extremely close proximity to my home electrical panel. A dedicated Topaz Ultra Isolation Transformer (model 91018-31T). This is a 1.8KVA model, with ultra low capacitance. I have my isolation transformer wired for balanced power output. A variety of upgraded power cords, ranging from a Pangea AC-14SE to an Elrod Power Systems EPS-3 Signature to a Sablon Audio Prince power cord with the beast of a Bocchino IEC connector on the Extreme end. (PENDING) A Synergistic Research Orange fuse (still trying to source one..will update when I do)  
    All other components (network, USB, mechanical) were left at their generic baseline. Playback was local content in Roon with HQPlayer (JPLAY ASIO driver) in a one box solution.

    Impact of Dedicated Circuit

    Going from a shared circuit to a dedicated 30A circuit, even with the generic power cord, the increase in speed and dynamics is absolutely stunning (wow!) but with perhaps a touch of edge or roughness. 
    When I first put in my dedicated circuits, it was dollar for dollar one of the best system upgrades I had implemented. That being said, the impact of a dedicated circuit on the Extreme is well beyond what I expected. Backgrounds are much blacker, and the physicality and control of dynamics are kicked WAY up. Details are more vivid and tangible, and depth resolution and spatial placement even more refined and extended. Everything that I was hearing before is simply better, faster, more controlled, and more coherent. Fantastic!
    I have two dedicated circuits (one for my DAC and analog components, one for my digital chain) for a reason. Consolidating my entire digital chain into a single box with the Extreme alone on a dedicated circuit is an absolutely wonderful place to be. Does power at the wall matter for the Extreme? Most definitely, most emphatically yes!

    Impact of Isolation Transformer

    Next I plugged my Topaz Isolation Transformer into my dedicated circuit, and plugged the Extreme (still with generic power cord) into the output of the isolation transformer.
    In my NUC reference system, I’ve found that the Topaz gives significantly darker backgrounds, and especially when run balanced, brings a sense of control and stillness between the notes that engages me immediately and consistently (that classic “midnight music listening” feeling, but any time of the day).
    Listening to the Extreme with the Topaz, playback certainly felt smoother (aligned with what I’m used to) and that slight edge and harshness I was hearing was tempered, but that incredible speed and dynamics that I was hearing with the Extreme was significantly diminished.
    As much as I love that “midnight music listening” feeling, I love the speed and dynamics of the Extreme even more. While the Topaz isolation transformer was certainly cleaning up some nasties, it was slowing things down too much, and simply was not able to keep up with the Extreme.
    As with all things power, every home situation and neighborhood situation is different. The choice between a power conditioner or power regenerator or large battery or isolation transformer or any combination of these will heavily depend on your home electrical setup, and what is going on in the electrical grid in your neighborhood. Experiment and see what works for you, but keep in mind that the better and faster and more power you deliver to the Extreme, the happier it is (think of it as a very large monoblock amplifier, not a computer).

    Impact of Upgraded Power Cords

    Still going directly to a dedicated circuit outlet (no isolation transformer...my digital audio Topaz is now officially retired), next I auditioned a series of upgraded power cords that I had available to me. I just a couple days before this listening test had received one of the traveling demo Sablon Audio Prince power cords (well broken in and very well traveled exterior) as a loaner, so I was excited to hear what it could do in my system.

    Going from the generic power cord to a Pangea AC-14SE, I immediately noticed a smoother presentation, with a slight(?) apparent loss in dynamics or speed (difficult to decouple some of the changes in my listening tests). There were significantly better dynamics and speed than I had heard with the Topaz isolation transformer. Certainly a very relaxed presentation, and a step forward from the generic power cord.
    With the Elrod EPS-3 Signature, there was a significant increase in speed and dynamics, with even better smoothness. The refinement of presentation and elegance reminded me of what I’ve heard in the finest analog systems, but with all the holographic engagement and transparency that I’ve come to love in my digital system. This was starting to get very very interesting indeed!
    The Sablon Prince is an interesting beast, with the HUGE Bocchino IEC connector on the Extreme end of the chain. Although it is labeled as “King” on my cable, the Prince has the Boccino connector on the IEC end and a normal connector on the plug end. The Sablon Audio King power cord has a Bocchino on both ends of the cable, but Sablon does not provide it for demos because of the impracticality of the monster connector on a wall outlet or power conditioner.
    Going from the Elrod to the Sablon Prince, the increase in speed and dynamics was immediate and striking. While still buttery smooth and elegant, speed and coherence made a massive step forward. My first 10 second reaction listening to the Sablon Prince is very similar to when I first heard the 2020 Sablon USB cable in my system: things just clicked and it sounded perfectly neutral and transparent, with incredibly coherence and dynamics, invisible and just right – “Yup, we’re done testing here...let’s enjoy some music”.
    Going back from the Prince to my generic power cord, the added edge with the generic cord is very clear, and the dynamics are quite a bit muted vs the Prince.
    Comparing the Prince direct to the dedicated circuit vs the Prince with the Topaz Isolation Transformer, I’m not hearing any improvement in background levels or smoothness, but significantly diminished speed and dynamics with the isolation transformer. Whatever conditioning benefit I’m getting from the Topaz seems to not matter with the Sablon in the chain (the Prince is taking care of business), but the Sablon seems to be able to provide more of the current that the Extreme craves.
    If the best cable is the cable that sounds like there is nothing there, the Sablon Prince is the closest I’m hearing to that with the Extreme and the cables I currently have available to me to test. Now the only decision is whether I purchase a Prince, or take a leap for the King without having had a chance to hear it!
    (NOTE: The Sablon Prince power cable is a loaner unit kindly provided by Mark Coles of Sablon Audio. I have no affiliation or association with Sablon Audio or Mark other than as a very happy owner of Mark’s 2020 USB cable. I’m under no obligations or expectations associated with the loaner unit, except to give it a listen, and pass it on to the next audiophile in the queue. My thanks to Mark for making this gem of a cable available to me!)
    Impact of Upgraded Fuse (PLACEHOLDER SECTION)

    The Extreme uses a single Schurter 4A fuse. Given the positive impact that other power tweaks have had, is there an upside to using something like the Synergistic Research Orange fuse? As I am able to source a Synergistic Research Orange fuse to audition, I will update this review.
    Impact of Upgraded Fuse (Updated August 2020)
    The Extreme uses a single Schurter 4A fuse. Given the positive impact that other power tweaks have had, is there an upside to using something like the Synergistic Research Orange fuse? After a bit of a pandemic-induced delay, I was able to source a 5A SR Orange fuse and try it with the Extreme.
    Note that the SR folks do highlight that the fuses are directional.  At the risk of having my alma maters revoke my electrical engineering degrees, I set aside the obvious questions (it’s AC power!) and took that as a given, inserting the fuse as recommended, with the “SR” reading in the direction of electricity flow.  For the Extreme, that means reading from the inside of the Extreme case toward the outside of the case.
    At first listen, there is indeed even more detail to be had, but with perhaps a hint more of harshness?  The general recommendation seems to be 100-150 hours to properly run in these fuses (the SR folks suggest as much as 200-300 hours), so time to let the stew stew a bit. After a couple days I was no longer picking up any harshness, and after a week, things were completely clean and smooth.
    This is my first time hearing the impact of “audiophile” fuses, but there is a welcome audible impact with the Extreme for me. Not at the levels I was hearing with (say) the Sablon Prince power cable, but a nice incremental lift in detail and relax-ness in presentation. Power really matters with the Extreme, and it is very easy (and quick) to hear when things are going in a better direction. To my surprise, that even applies to fuses.

    Network Optimizations

    Again a reminder, my tests so far of the Extreme have been with a generic Cat 5 ethernet cable connected to a shared SMPS-powered generic switch in my media console, connected over a length of generic Cat 5 home ethernet to an Ubiquiti EdgeRouter 10X home router connected to an AT&T-provided optical network terminal and Pace gateway/router for my fiber internet connection.
    As I noted above, in this configuration there was a notable gap between content played from local storage on the Extreme and content from on my home Mac Mini file server. There was also a much bigger step down to content streamed from TIDAL.
    Can we make these gaps smaller or even go away by providing the Extreme with better copper networking, switching to optical networking, and/or a more direct path to my fiber internet connection?
    Starting at the back panel of the Extreme, I evaluated the following network upgrades:
    A variety of upgraded ethernet cables, from the surprisingly good Cable Matters SFTP Cat 8 cable and the even better Monoprice Cat 8 cables to the brand new Sablon Audio 2020 Panatela Reserva ethernet cable that arrived just in time for this review An Uptone Audio EtherREGEN network switch with Uptone Audio UltraCap LPS 1.2 power supply, with the Extreme on the recommended “B” side of the network isolation moat An EtherREGEN with a Planet Technology MGB-TLX SFP fiber transceiver on the SFP port on the “A” side of the EtherREGEN, connected to the StarTech PEX1000SFP2 PCIe optical network card in the Extreme (with a matching Planet Tech optical transceiver) A Sonore opticalModule fiber media converter (FMC) powered by an Uptone Audio LPS 1.2 power supply, with two Planet Technology transceivers, converting wired ethernet to optical ethernet connected to the Extreme’s StarTech optical network card A Sonore opticalModule connected all the way back to a Ubiquiti EdgeRouter 10X gateway/router (bypassing all the intermediate home ethernet wiring and switches) with a long optical fiber run to the Extreme Various power and topology optimizations for the AT&T provided Pace 5268ac router/gateway and Alcatel-Lucent G-010G-Al optical network terminal (ONT) for my optical-fiber-based Internet connection  
    For these tests, I left the Extreme plugged directly into my dedicated 30A circuit with the Sablon Audio Prince (I can’t give that up now that I’ve heard it), but with the original generic USB and mechanical baseline setup. Playback was local content, file server content on my Mac Mini, and TIDAL content, all played through Roon with HQPlayer (JPLAY ASIO driver) in a one box solution. 
    For the component level tests, I limited my testing to TIDAL streaming content only to force music to stream from the Internet through all the intermediate network connections and devices. When I got to an optimal configuration for streaming, I came back to compare streaming to file server content to local content with an optimized network.

    Impact of Ethernet Cables

    When I first received my Uptone Audio EtherREGEN, I was stunned by the sound quality impact network connectivity could have. As surprised as I was by the impact the EtherREGEN was having, I was shocked at how incredibly audible differences between ethernet cables were. I have no idea how and it is a difficult conversation to have even with dedicated audiophiles, but for me, with the EtherREGEN I could tell apart ethernet cables with just a couple seconds of listening. Incredible, and an experience that forced me to reconsider a lot of things that I had taken as givens.
    In my experiments with the EtherREGEN, with better shielding and higher bandwidth cables (Cat 8), timing detail, coherence, and sense of space were all significantly improved. If you’ve stood next to a live musician as they are playing a bass or a low string instrument, you know the whole body feeling you get from the strings and soundboard. With the EtherREGEN and better (not more expensive, but electrically better) cables, that whole body feeling was very real, and added significantly to the sense of being in the presence of the musicians. 
    As an added benefit, on some of my best recordings, the low space resonances from the room where the recording was made all snapped into focus for me, giving me a very strong sense of the space where the recording was made. That feeling of being in the cathedral or the club or concert hall is awesome. The icing on the cake was that I was able to hear all this with the EtherREGEN and inexpensive but quality Cat 8 ethernet cables ($10-15 range).
    Even without any attention to network or cables, I was hearing hints of that same whole body feeling with the Extreme (first time hearing it without the EtherREGEN). Using my generic media console network switch, as I went from generic Cat 5 ethernet cable to a Cable Matters and Monoprice Cat 8 cable, I heard a very slight improvement in bass detail going from generic Cat 5 to Cable Matters and Monoprice Cat 8. 
    However, even in this configuration, things significantly opened up and became more natural sounding with the Sablon ethernet cable. This was a surprise, given the cruft before the cable., but even in this configuration cables do have an audible impact with the Extreme (a very non-subtle and welcome impact with the Sablon 2020 cable). Bass control and sense of space definitely has moved to the positive with the Sablon.
    Given how small the impact was in this configuration going from generic Cat 5 to the Cat 8 cables, I was quite surprised at the impact of the Sablon ethernet cable, even with all the other ethernet cables in the chain. Could this be a hint as to how to get the most out of the Extreme with copper networking?
    (NOTE: The Sablon 2020 Ethernet cable is a loaner unit kindly provided by Mark Coles at Sablon Audio. I have no affiliation with Sablon Audio except as a customer, with no expectations or obligations for the loan of the cable except to give it an audition in my system.)

    Impact of EtherREGEN for Copper Ethernet Regeneration

    In this test, I introduced an Uptone Audio EtherREGEN to the chain. The EtherREGEN (see Rajiv’s comprehensive review here) is an audiophile network switch that provides both ethernet signal regeneration, and a signal isolation “moat” between it’s “A” side and a single RJ45 100mbps network port on its “B” side. For these tests, I powered the EtherREGEN with an Uptone Audio LPS 1.2 power supply set to 12V.
    My experience with the EtherREGEN with my reference NUC setup was outstanding. Does it add anything to the Extreme, even though the network speed going to the “B” clean side is reduced to 100 megabit ethernet? 
    To test, I compared the Extreme connected to the “B” clean side of the EtherREGEN (with a premium ethernet cable) and the EtherREGEN connected to a generic switch from the “A” dirty side with a generic Cat 5 cable, with the Extreme connected to the generic switch directly with a premium ethernet cable.
    The answer is a most definite yes. All the attributes that I heard before with the EtherREGEN are back - increased speed and control (especially for bass), more subtlety and detail, awesome openness and sense of space.
    Repeating my ethernet cable tests, but this time with the EtherREGEN in the chain, I was able to hear how really special the Sablon 2020 ethernet cable is. Just lovely - neutral, transparent, coherent, fast, and relaxed presentation. Quite a stunning improvement over the Monoprice Cat 8 cable, which was my prefered cable with the EtherREGEN in my NUC-based chain. The music and the room around the musicians just draws you in. Like my “first 10 seconds” reaction when hearing the Sablon 2020 USB cable and Sablon Prince power cord, the Sablon 2020 ethernet cable comes across as neutral, transparent, coherent, invisible and just right – “Yup, we’re done testing here...let’s enjoy some music”. Mark is really on a roll, and I’m loving everything I’m hearing from him.
    So what is going on with the Sablon ethernet cable that is resulting in this striking level of impact? The Sablon cable is quite impressive, with Cat 8.1 Telegärtner connectors, robust shielding, and Mark’s favorite conductors. These connectors are distinguished by extremely high bandwidth (bandwidth seems to be emerging as a key measure for ethernet cables and audio). Mark uses his favorite conductors for the body of the cable itself, with 5 layers of shielding. Is the extreme bandwidth + shielding + conductor quality what is creating this synergy with the Extreme? Clearly, the Sablon ethernet cable is keeping up with the Extreme much better than the other Cat 8 cables I have on hand. Even for cabling, speed seems to make a big impact with the Extreme.
    Hearing what the EtherREGEN is able to do with the Extreme, I’m reminded again of what an outstanding value the EtherREGEN is for wired ethernet (just lovely...I had to pull myself away  from the combination of Extreme + EtherREGEN + Sablon 2020 ethernet cable to continue with testing). How will moving to optical ethernet change things?

    Impact of Using EtherREGEN as a Fiber Media Converter

    Note that Emile did help to configure my optical network interface with some experimental tweaked parameters and driver configurations. The tweaks included configuring the optical network connection for Microsoft Client Network, File and Print Sharing, and IPv4 only. Also, disabling most of the advanced features in the Realtek PCIe GBE driver, and tweaking some buffer sizes to what Emile believes sounds better with “thin” sounding networks. All my listening tests with optical networking were from this baseline, and I did not experiment with optimizing any of these parameters myself (even my audio nervosa has its limits). I made no changes to the copper networking interfaces, which were already tuned from the factory.
    The Extreme is my first exposure to optical ethernet. I have held off doing experiments with optical ethernet as I’ve been waiting for the Extreme, knowing that the optical network interface is generally the preferred interface on the Extreme. For these tests, I picked up a pair of the Planet Technology MGB-TLX optical transceivers that Emile had recommended from his tests. I also used the Sablon 2020 ethernet cable from my generic media console switch to the EtherREGEN.
    The EtherREGEN does have an SFP port for an optical transceiver on the “A” “dirty” side. This allows optical in on the “A” side, and copper out of the “A” side or “B” “clean” side to the Extreme. It also allows copper into the “A” or “B” side of the EtherREGEN, and optical out to the Extreme from the “A” side (the EtherREGEN is symmetric, and can be operated in either direction). The later configurations are what I evaluated, basically using the EtherREGEN as a Fiber Media Converter (FMC), but with a moat (with the 100mbps ethernet limit from going across the moat) and without a moat (with the full 1gbps ethernet on the “A” side).
    For the first test, I wanted to compare wired ethernet to optical ethernet on the Extreme. For this test, I used a generic ethernet cable to connect the “A” side of the EtherREGEN to my generic media console network switch. I then I compared wired ethernet from the “B” side of the EtherREGEN to the Extreme with the Sablon 2020 ethernet cable (the optimum configuration from the previous section), to optical ethernet from “A” side of the EtherREGEN to the optical interface of the Extreme (no moat but fast ethernet for optical, vs moat but slower ethernet for wired).
    With the optical input to the Extreme, detail and control and dynamics all stepped up significantly. The sense of space and tangibility was improved as well. No question, even without the isolation moat of the EtherREGEN, the optical network path with the EtherREGEN is a huge step up from wired ethernet.
    But how much of that is due to the slower ethernet speeds when you step across the EtherREGEN moat, and how much to the optical path directly? To test that, I rewired the network to use the Sablon 2020 ethernet coming from my generic media console switch to the EtherREGEN, with optical going from the “A” side of the EtherREGEN to the Extreme. 
    By connecting the Sablon ethernet cable to the “B” side of EtherREGEN, I would get the advantage of the moat but with slower ethernet speeds. By connecting the Sablon ethernet cable to the “A” side of the EtherREGEN, I would get fast ethernet speeds but no moat. In both cases, the final leg would be optical to the Extreme (moat but slower ethernet for optical, vs no moat but faster ethernet for optical).
    In these configurations, optical with the moat is better than wired, but it is still a definite step down from what I’m hearing with both optical and wired on the same side of the EtherREGEN (no moat). 
    For me, optical ethernet is clearly the winner, but so is fast ethernet. Whatever the EtherREGEN isolation moat is bringing to table isn’t making up for what is being lost with the step down in ethernet speeds.  To my ear, the EtherREGEN moat just can’t keep up with the Extreme. Once again, speed seems to really matter with the Extreme.

    Impact of Using a Sonore opticalModule as a Fiber Media Converter

    During my tests with the EtherREGEN and optical, my unit was running quite hot (presumably from the extra power draw of the optical transceiver?). While Uptone notes that the unit is designed to run hot, it did get me thinking that by not using the signature moat feature of the EtherREGEN, I was basically using the EtherREGEN as a high quality John Swenson designed audiophile fiber media converter. 
    The other John Swenson designed FMC on the market is the Sonore opticalModule – wired ethernet in on one side, optical transceiver and optical output on the other. So how does the EtherREGEN with optical and wired ethernet on the “A” side compare with the opticalModule as a FMC? I compared them with each powered by an Uptone Audio LPS 1.2 power supply (12V for the EtherREGEN, 5V for the opticalModule), with the Sablon Audio 2020 ethernet cable going to my generic media console network switch.
    While differences were less obvious on initial listen, the opticalModule is clearly and consistently better sound quality to my ear. The longer I listened to each configuration, the more clear and compelling the differences became. With the opticalModule, there are definitely more dynamics and control, better and more subtle sense of detail and space, and most importantly for me, a more relaxed and engaging presentation. 
    Reviewing my notes from when I first received my EtherREGEN and went through power supply and ethernet cable tests, the character of the differences I hear between the EtherREGEN and the opticalModule are very similar to what I experienced with the EtherREGEN as I moved from the stock EtherREGEN power supply to a Uptone Audio LPS 1.2 to a Paul Hynes SR4. As I improved power to the EtherREGEN, the EtherREGEN just opened up more and there was more goodness there.  Going from the EtherREGEN to opticalModule is just more goodness in that same direction and of that same type.
    My suspicion is that the opticalModule may be straining the LPS 1.2 less than the EtherREGEN is straining the LPS 1.2 (in the past, I’ve found that sound quality can be adversely impacted as the LPS 1.2 is driven closer to its current limits...it’s a wonder supply for low power devices, but has its limits as pushed). With the opticalModule running cool and effortlessly and beautifully I did not chase this further, but EtherREGEN owners may be well served to seek out high quality higher current capability power supplies if they are running the optical networking with the EtherREGEN.

    Impact of Network Optimizations All the Way Back to My ISP Connection

    The Extreme definitely rewards the listener who pays careful attention to network optimization – give the Extreme the cleanest fastest network bits you can, and it just opens up more of what the Extreme is capable of.
    All my tests to this point have had a lot of other cruft between my fiber link to the street and the Extreme. What happens if you eliminate that cruft and take network optimization all the way back to your connection to your internet service provider?
    As background I have AT&T fiber optic internet service to my home (1gb up and down). I have fiber optic coming in from the street to an AT&T provided Alcatel G-010G-A optical network terminal (or ONT, basically a fancy fiber media converter that also handles video signals and voice signals). That ONT is connected by ethernet to an AT&T provided Pace 5268ac router/gateway (WiFi, VoIP, TV, Ethernet). I only have data to my home (no voice or traditional cable), so the only thing I connect to the AT&T Pace gateway/router is my Ubiquiti EdgeRouter 10X. On my EdgeRouter, I have multiple VLANs (guest, IoT, home, etc), my WiFi access points, and all my wired ethernet for my home.
    So what happens if I move my opticalModule to my closet and connect it directly to my EdgeRouter? The Planet Technology optical transceivers I’m using are rated to 12 miles(!). The long fiber run from my listening room to my network closet is considerably less than that.
    With the intermediate Cat 5 home network and generic media console switch out of the path, sound quality took a significant step up – more openness, more control and detail, just more of the network goodness I’ve been hearing each step of the way.
    How about getting rid of the AT&T router/gateway and connecting directly to the ONT? Alas, AT&T requires that you use their gateway and does not provide any bypass mode (yes that really sucks). Thankfully, the authentication mechanism AT&T uses for their router/gateway isn’t terribly sophisticated.
    Subscription is managed at the ONT (you can’t easily steal service), but if you clone the MAC address of the AT&T provided gateway to your own router, you can swap in your own router after the AT&T router/gateway has authenticated against the AT&T network. For the more adventurous amongst us, it is also possible to extract the security certs from the AT&T router/gateway and install them on your own router with a WPA supplicant. I would never endorse such a thing (ahem), but it is an opportunity to see if eliminating another block in the network chain has any impact.
    Hypothetically speaking, if one were to eliminate the AT&T provided gateway, yup another notable step up in sound quality, with more of the same goodness. What I’m (hypothetically) hearing is stunning, by far the most relaxed and natural and extended soundstage and dynamics I’ve ever heard. 
    Swapping out the SMPS on the EdgeRouter for a LDPWR DXP-1A5DSC dual stage power supply at 12V, energized by a PowerAdd Pilot Pro2 battery? Wow, quite a bit better still. Swapping out the generic ethernet cable between the ONT and the EdgeRouter with the Monoprice Cat8? Yup, even better. Swapping out the SMPS on the ONT for a LDPWR DXP-1A5S single stage power supply at 12V, energized by a PowerAdd Pilot Pro2 battery? Another material step up (this one really surprised me...time to hack into the AT&T fiber concentrator down the street and finagle a power supply upgrade?).
    As a final bonus tweak, how about the router noise filtering dongle thingie that Mark Coles sent along with the Sablon 2020 Ethernet cable to demo? Yup, even better. Dang, this rabbit hole seems to have no end to it.
    I should note that the EdgeRouter is a fine gateway/router (the price/performance/feature set is pretty amazing actually) but the real bonus is that unlike the AT&T provided Pace gateway/router, it can be easily powered by a modest high quality power supply like the LDPWR’s or a LPS 1.2. Clean power to the AT&T provided ONT and the EdgeRouter 10X made a startling difference in sound quality. I was anticipating a small change for the better, but it was a heck of a lot more than that.
    Aside from telling me I’m going to need two Sablon 2020 ethernet cables (ONT to EdgeRouter, and EdgeRouter to opticalModule), all this is telling me that there is probably even a win to be had by getting an additional router/switch, and optically isolating my EdgeRouter 10X from the rest of my home network. In this configuration, I’d have a LPS powered ONT to LPS powered EdgeRouter 1, which is then optically connected to the Extreme and optically connected to a SMPS powered EdgeRouter 2. The EdgeRouter 2 would then be connected to my WiFi and the rest of my home network. 
    That would give me a minimal network path from the street to the Extreme, with fiber, LPS, and pretty good galvanic isolation from the rest of my home network. For now, that’s a journey for another day, and a different corner of this particular rabbit hole waiting to be explored.

    So After All That, How Does Local Storage vs File Serve vs TIDAL Compare?

    With all the same caveats before of not knowing the masterings on TIDAL, how do all these music sources compare after all these network optimizations?
    Sound quality is danger close now, enough so that I can much more clearly identify TIDAL songs that are different mastering than what I have locally on my Extreme and on my Mac Mini file server. I still give the SLIGHTEST of nods for dynamics to local content, but we’re into a level of nuance that is almost disrespectful to the astonishing sound quality and musical performances I am hearing.

    Closing Thoughts on Network Optimizations

    Taking a step back, not only am I astonished at what I’m hearing with networking changes, but I’m even more astonished that I am able to hear it at all. For all my hopes that jumping to an end game digital server would put an end to the system optimizations, the Extreme is so astonishingly revealing and performant that everything you feed it (power and network) is holding it back in some way. 
    The only other “True Reference” component I’ve experienced like this is an mScaled Chord DAVE – Both DAVE and Extremes represent (to me) an absolute reference that you can only take away from. Put the effort in to feed the Extreme better inputs (power and network), and you will be rewarded handsomely way beyond your wildest expectations. 
    So how about focusing some care and attention to the output side of the Extreme?

    USB Optimizations (limited)

    Believe it or not, all my testing so far has been done with a generic printer-class USB cable between the Extreme and my DAC. Unfortunately, I have recently gone through a major investigation and upgrade cycle for USB with my NUC reference system, so I have limited cables and USB tweaks to be able to test with Extreme. Fortunately, these are the best I heard on my NUCs, so let’s dive in.
    What is there to be gained by optimizing the critical USB connection between the Extreme and your DAC?
    Starting at the back panel of the Extreme, I evaluated the following USB upgrades:
    A variety of upgraded USB cables, from my reference and favorite Sablon Audio 2020 USB cable, to the Uptone Audio USPCB and Monoprice SlimRun optical USB extension cable A maxed out SOtM tX-USBultra Special Edition powered by a Paul Hynes SR4 power supply  
    For these tests, I left the Extreme powered and networked in my optimal configuration described in previous sections. I also limited testing to content stored locally on the Extreme.

    Impact of USB cables

    My first test was to compare the generic USB cable with my reference Sablon 2020 cable. In previous testing, I had iterated through many USB cables (including DIY shielded cables) before settling on the Phasure Lush^2 cables (with DIY layered on top of those as well). I was amazed at how different materials and shield configurations had such a profound impact with USB cables.
    When Sablon Audio released their 2020 update to their USB cable, it received rave reviews from many ears that I trust so I ordered one unheard. As I have mentioned earlier in this review, 10 seconds into my first listen with the Sablon, I was done experimenting with USB cables and shielding and put all that stuff away. The naturalness and transparency and relaxed presentation of the Sablon 2020 USB cable was perfect (no compromise) for me.
    It’s taken several weeks of listening tests with the Extreme to finally get here, but I was very eager to finally hear how the Sablon 2020 USB cable sounded with the Extreme. Dropping it in, I had that same “first 10 seconds” reaction all over again. Just a wonderfully engaging and welcoming natural presentation, incredibly detailed, but effortless and without any stress. This is the most invisible and transparent USB cable I’ve ever heard, and I’m hearing it all over again. Such a delight, and in the world of audio nervosa, such a gift to completely trust a component like this and know it is just right (I’d missed this cable more than I knew). 
    Alas, I do not have access to other well regarded USB cables (like the Shunyata Sigma USB cable) to test, but if someone is willing to share, I’d be delighted to give them a listen and update this review.
    The second USB cable discovery that allowed me to end my USB experimentation came from a fellow audiophile who’s ear I not only completely trust, but whose bias toward transparency and presence aligns extremely well with my own. He suggested that I audition the Monoprice SlimRun optical USB extension cable, which turned out to be gold. The Monoprice SlimRun converts the USB signal to an optical signal, and at the other end has a female USB connector that converts it back to regular USB. It is available in lengths up to 160 feet, so it gives tremendous flexibility in where you place your music server (and creates some distance from your DAC for any RF generated by your server). 
    The Monoprice SlimRun is not quite galvanically isolated, since there is a power line for the end connector and USB Vbus that runs the length of the cable, but there is an option to externally power the cable with a micro USB connector on the computer end of the cable. Powering the Monoprice USB SlimRun with an Uptone Audio LPS 1.2, you get all the essential benefit of galvanic isolation, but with USB data rates (no compromise), and cable lengths as long as you practically could hope for, with no apparent sound quality changes with longer lengths.
    The Monoprice SlimRun is a USB extender, so It does require a USB cable to connect to the DAC at the end of the extension run. I variously use the Uptone Audio USPCB (an astonishingly good value device, made incredibly practical with the Monoprice SlimRun) and the Sablon Audio 2020 USB cable.
    Comparing the Sablon Audio 2020 USB cable direct from Extreme to my Chord DAVE vs Sablon USB cable with the Monoprice SlimRun, the SlimRun (powered from Extreme) does add a touch of harshness to playback. Switching power on the SlimRun to a PowerAdd Pilot Pro2 battery cleaned that right up, giving the same wonderful presentation I’m used to. When I cheated and reclaimed a LPS 1.2 from my network router, things got much cleaner and got me to my end state.
    Comparing the Monoprice SlimRun with Sablon USB cable vs the Uptone USPCB, I give the edge to the Sablon for all the reasons I cited earlier. Simply delightful.

    Impact of USB Regeneration

    With my NUC music servers, I heard tremendous benefit with USB regenerators like the Uptone Audio ISO Regen. Prior to getting the Extreme, I found my end game USB regenerator with the SOtM tX-USBultra Special Edition. The impact this had with my low power NUCs was magical, and it scaled wonderfully with the best power supply I had available (a Paul Hynes Limited SR4 @ 12V).
    Placing it in the chain with the Extreme seemed to actually slow down the remarkable speed and dynamics of the Extreme. As good as the tX-USBultra SE is (and it is one of the crown jewels of audiodom), amazingly it seems like it is holding back what the Extreme can do natively. 
    To get a meaningful USB upgrade for the Extreme, it may be necessary to jump to something like the JCAT USB Card XE or JCAT USB Card Femto, paired with some high quality power supply or perhaps the spare +5V supply in the Extreme. I look forward to auditioning these at some point in the future.

    Mechanical Optimizations

    I have become a big believer in mechanical and vibration isolation for any power supply and any piece of digital equipment (particularly DACs). With the astonishingly small signal levels that we’re impacting and hearing, even small vibrations will induce noise and reference power instabilities that are surprisingly audible. 
    Particularly with the Chord DAVE, that remarkable sense of depth and holographic space that I treasure so much is the most susceptible to vibrations. Rob Watts, the talented and always insightful designer of the DAVE attributes this sense of depth with the DAVE to extreme fine signal level noise reduction. I’ve learned to key off that sense of depth and space to identify when things are not what they should be. 
    The design of the Extreme reflects a significant and extremely thoughtful focus on mechanical stability and vibration isolation, particularly for key components in the power supply. When it comes to power supply stability and reference voltage stability, I’ve found that even seemingly small improvements in vibration isolation can have an outsized impact (as Emile has so succinctly explained, a voltage applied to a capacitor causes it to vibrate, and vibration applied to a capacitor causes it to generate a voltage).
    With that background, out of the box I intentionally gave little attention to vibration isolation with the Extreme. As I noted earlier, Emile has already gone to tremendous lengths with the case work and internal vibration isolation around key components in the power chain (I’m blown away actually...that level of attention to detail in a commercial offering is way beyond anything I’ve seen before). For my testing to this point, I’ve had my Extreme inches away from a speaker on a generic media console with no effort put into vibration isolation, with nothing but a Pottery Barn towel under the Extreme.
    So starting from here, I wanted to test the following:
    Take advantage of the flexibility of the Monoprice SlimRun USB extender to move the Extreme to the corner of the room, placed away from speakers and my DAC, directly on a wood floor Add a double stack of Taiko Audio Daiza vibration isolation platforms under the Extreme  
    For these final tweaks, I kept the Extreme in its optimal power and network configurations, and used the Monoprice SlimRun USB Extender and Sablon 2020 USB cable to connect the Extreme to my Chord DAVE DAC from a distance.

    Impact of Moving Extreme to Edge of Room and Onto Daiza Vibration Control Platforms

    First order of business was to cajole my daughter and partner out of their rooms with even more chocolate, and impose on them to help me lower the Extreme to the floor. Once there (and toes safe), I used some furniture movers and lots of huffing and puffing in very tight quarters to get the Extreme happily in its new home:

    The flexibility one gets with optical fiber networking and the Monoprice SlimRun optical USB extender can not be overstated. I could have put the Extreme virtually anywhere in my listening room, or even in any room in my house (the only restriction I had was proximity to my dedicated circuit power outlet). In the end, it puts a smile on my face to see a 100 pound music server capable of such astonishing music reproduction nestled under a century old Steinway (and until post Pandemic when we have house guests again, I can get away with having it there.
    I placed my Extreme on a double stack of Taiko Audio Daiza vibration damping and control platforms. The platforms are beasts of precision milled 25 pound slabs of panzerholz, with an intriguing crop circle spiral pattern milled on the underside and substantial copper and panzerholz footers.
    (Photos used with permissions from Taiko Audio website)
    Getting the Extremes stacked on the Daiza’s in this tight space was (to say the least) EXTREMELY challenging. Thankfully no fingers were crushed, no disks were ruptured, and no scratches were scratched. Alas, given the pain of getting things in place (and the laughter of the folks eating chocolates and watching me suffer), my willingness and ability to test different configurations (one vs two Daizas, etc) and do proper A/B listening tests is basically zero. Post Pandemic, I’ll be delighted to host a listening session where someone (else) is changing the configuration while I do critical listening for audible changes.
    All that being said, this panzerholz is pretty remarkable material (this is my first in person exposure to it). Panzerholz was first developed during World War II as a modest-weight armor material for tanks and other vehicles. By taking multiple layers of laminated wood, and compressing it under tremendous heat and pressure and steam to ~½ its size, the material becomes an ultra dense cellulose laminate which is actually bulletproof(!)
    For audiophiles, panzerholz is compelling for its vibration dampening properties. By combining very high density with a low transmissibility and high internal damping, panzerholz is used for everything from piano soundboards to turntable bases and tone arms and cartridges to case work to vibration isolation.
    For the Daiza, Taiko has taken the panzerholz that they strategically use internally to the Extreme, and built a vibration control platform that complements the design of the Extreme case itself. The crop circle spiral pattern on the underside is intended to tune the natural modes of the platform, with additional damping with the foam filled foundations for the footers and in the foam filled copper and panzerholz footers. The mechanical properties of the Daiza are engineered to be a complement to the aluminum case work of the Extreme, dampening the high frequency resonances of the casework while minimizing any self resonance (dampening rather than ringing). Emile and others have also noted the compound benefit of stacking Daizas, offering better damping and vibration absorption.
    As I learned more about the unique material properties of panzerholz (and how it side steps a lot of the unintended challenges with other materials and vibration isolation strategies) and learned about the care that had been put into designing the Daiza as a mechanical complement to the Extreme, I took the leap and ordered a stacked pair for my Extreme, and a smaller Daiza for my Chord DAVE.
    When I first got the Daizas, I was struck by how they felt physically, and how evocative they were. They had a wonderful warmth of wood, but with a density and stillness that was striking (almost like holding a dense deadened metal block, but with warmth and tactile inviting feeling of wood). Placing a smaller Daiza under my Chord DAVE, the impact was very immediate and tangible: much more imaging clarity and detail (classic benefits from vibration isolation for my DAC), but also a calm and stillness that I found to be very compelling and engaging, and even comforting. This additional sense of calm was a new experience for me, and not something I had heard with other vibration isolation materials and schemes.
    Assessing the impact of the Daizas with the Extreme was more difficult. Given the newness of my experience with the Extreme and the enormous challenge of placing a 50 pound stack of panzerholz under a 100 pound beast of a server in a very tight space, it is very difficult for me to speak with specificity to the differences I am hearing with the Extreme on 0, 1, or 2 Daizas (for practical reasons, I jumped right to two, and I’m not touching the stack again until I hit the gym for a couple months in preparation). However, the end result of all the tweaking is a calm, ultra fast yet ultra controlled presentation that feels simultaneously effortless and incredibly powerful. 
    I’m grasping for analogies for what I am hearing, but I am reminded of the finest dancers, who have an incredible quiet grace and control that seems both absolute and absolutely effortless. They also evoke a quiet power that can explode at any moment into spectacular movements. As I reflect on and relish what I am hearing and experiencing, the Extreme on Daizas evokes that beautiful sense of being in the presence and in the moment with that remarkable dancer.
    So with the Extreme all tweaked out and optimized, how does it sound? In Part 5 (LINK) I share notes from extended listening sessions, and bring it all together to close out this review.
    Community Star Ratings and Reviews
    I encourage those who have experience with the Taiko Audio SGM Extreme to leave a star rating and quick review on our new Polestar platform.
  4. Upvote
    Gavin1977 reacted to ray-dude for an article, Reality Quest: Going to Extremes with the Taiko Audio SGM Extreme (Part 1 of 5)   
    Editor's Note: This week Audiophile Style is going to extremes. In fact, we are calling it Extreme Week here on AS. Three months ago when I first talked to Ray about publishing a review of the Taiko Audio SGM Extreme, I had no idea he would put an extreme amount of work into the effort and put together a treatise on his experience. When I read through it the first time, I knew we had to do something different. Thus, we have dedicated an entire week to publishing Ray's review of the SGM Extreme. One part each day, Monday through Friday. I hope the AS Community enjoys reading this review series as much as I have. - CC
    Reality Quest: Going to Extremes with the Taiko Audio SGM Extreme (Part 1 of 5)
    A back (and bank) breaking 100 pound $26,000 digital music server with 40 Xeon cores and 48GB of custom memory and 8TB of M.2 PCIe storage, unironically named “Extreme," with a reputation for being the ultimate mic-drop Summit-Fi for digital audio? Wow...

    So what is audiophile life like at these rarified heights? How does the Taiko Audio SGM Extreme stack up against an already OCD-tuned and optimized NUC digital music server/endpoint setup? Can one possibly justify this sort of expense and extravagance for a music server? If one were crazy enough to take this leap, are there ways to improve upon Extreme and take its performance higher still?

    Earlier this year, semi-rationalized irrationality got the best of me, and I decided I needed the answers to these questions. Many emails and discussions with audiophile friends and Taiko Audio guru Emile Bok later, I took the leap and ordered an Extreme.

    Alas, a month later the world changed, and after a brief Pandemic-induced supply chain and shipping delay, I received my Extreme and have been putting it through its paces ever since.

    TL;DR – It’s pretty damn awesome!

    (TL;DR)2 – Here is where I ended up after all the tweaking.

    In many ways, the Taiko Audio SGM Extreme represents the culmination of many years of community learnings about computer audio and computer audio optimization. Each aspect of the Extreme (physical, electrical, mechanical, compute, I/O, software, etc.) is taken to the (no pun intended) absolute extreme, all in the carefully designed and considered service of digitally reproducing the best sound possible.

    The Extreme is Emile Bok’s opus, a seminal product that is the distillation and embodiment of the state of the art in digital audio. Even for those that have not been able to hear it first hand, the Extreme offers much to appreciate, and especially for system designers and DIY types, much to learn from.

    To give each aspect of the Extreme the attention it deserves, this review is broken up into 5 parts:
    Part 1 - Introduction and Digital Audio Optimization Foundations In this part, I share my personal perspective and journey with digital music servers, and how those experiences and biases inform and color my experience of the Extreme. I also share details on equipment under test and the music I typically use when evaluating new components and systems. Those well-steeped in the practice and lore of digital music server optimization may wish to jump straight to Part 2.  
    Part 2 - Enter the Extreme With the Extreme, the component selection, casework, power and mechanical design, system configuration, and numerous design details all reflect a deep understanding of system design and a thoughtful care for how all the pieces come together into a whole that is much greater than the sum of the parts. In Part 2, I dive into Emile’s masterwork, and break down these pieces and explore how they work together.  
    Part 3 - First Impressions and Basic Configuration In Part 3, time to listen to some music, and see what the Extreme is able to do straight out of the box.  
    Part 4 - Tweaking Up the Extreme In Part 4, it is time to take the Extreme from Ridiculous Speed to Ludicrous Speed to Plaid! How does careful attention to power, networking, USB, and mechanical factors impact the performance of the Extreme? It turns out, quite a lot!  
    Part 5 - Extended Listening Impressions, Learnings, and Conclusions And finally in Part 5, time to put the A/B tests and audio nervosa tweaking twitches away, really listen to some music, and reflect on how all these technologies come together into what is truly a remarkable experience of music.
    Let’s dive into Extreme week!
    Digital Audio Optimization Foundations

    Digital optimizations and hygiene in digital audio can be a contentious topic (bits are bits, right?). Rather than debate mechanics, I am sharing my experiences in my home with my equipment with my ears and my biases and my aspirations for connecting emotionally to remarkable musical performances. Almost certainly yours will vary. Hopefully my experiences are helpful to you, but if not, that’s OK too.

    What matters for me is how the notes come together to something larger, a resonance that is greater than the sum of its parts. As an imperfect analogy of that “something larger” experience, consider how mixing coal + chalk + water + iron filings in ever more precise proportions using ever more esoterically sourced materials won’t result in a child that you will cherish and adore and make the center of your life. Both your child and the coal + chalk + water + iron filings are made of the exact same things. Arguing about the purity of the water or where the coal was sourced or the magnetic properties of the iron for me changes nothing. The real debate is how they come together, and how it comes alive and becomes meaningful.

    A few years ago, I was introduced to the Chord Mojo and then the Chord DAVE, and they have completely changed my experience of music. For the first time I've gone from “listening to music” to “participating in a performance”. That feeling of intoxication or euphoria from the performance has been driving me to optimize my analog chain, and now to go deep into the digital side of my chain.

    When a recorded performance truly comes alive, it draws me in the same way I am drawn to an amateur performance in a coffee shop or a subway. This sense of reality is difficult to describe, but it is only loosely correlated to what I think of as “typical” measures of distortion or tonal balance. When I am walking by a coffee shop, I can tell if there is live music being played inside (vs recorded music). Even with all the traffic noise and going through walls and glass, I can somehow tell it is real people with real instruments even from the street, and I am attracted to it and want to listen.

    That has nothing to do with our normal measures of tonal balance and noise floor or sound stage or imaging clarity or being in the sweet spot. The music coming from inside the coffee shop sounds like crap (by any normal audiophile measures), but it still sounds (and is) real. Somehow, our brains know how to deal with the natural distortion of real noises that are going through walls and barriers and overcome background noises, and to focus on the "real". When that “real” clicks in, for me it is a fairly abrupt transition, and my experience of music steps up to a completely new (and intoxicating) level.

    On the digital side, Chord DACs (and especially the Chord DAVE) are by far the best I’ve heard at creating this sense of reality. After I heard the Chord Mojo, I ordered a Chord DAVE unheard, and have since rebuilt my entire system around the magic that the DAVE is able to deliver.

    On the analog side, I’ve discovered that the more I got rid of, the more transparency I discovered and the more reality I was able to experience from the DAVE. I’ve replaced my beloved B&W 802d3’s (and associated amps, etc.) with high efficiency single driver Voxativ 9.87’s with 104db sensitivity Voxativ 4D drivers. My DAVE, with its lowly 2W output, can drive these speakers to ear splitting levels. More importantly, I’ve been able to eliminate amps and crossovers, having DAVE wired directly to a single ultra fast and ultra sensitive point source driver.

    The end result is an experience that is holographic, astonishingly quick and controlled, and extraordinarily immersive. The level of transparency and reality is intoxicating, and remarkably revealing of everything in the chain: any weakness or system stumble takes away from that sense of reality. How to preserve as much of that sense of “real” as possible? How to get more? With my analog and digital-to-analog system anchors in place, my attention shifted to the digital side.

    My digital audio journey has been driven by the core principle that any digital optimization must start and end with the DAC. Obviously, if one is starting with bit-perfect sources (and if you’re not, fix that), these bit-perfect bits are not affected at all by any digital optimizations (if bits were being changed, you would hear very audible pops clicks and drop outs). Any sound quality change you hear is due to something in your digital chain somehow and in some way impacting your DAC (even if you have no idea how or why).

    For me, the core question for digital hygiene and optimization is what can be done to the digital chain to minimize anything being injected into or induced in the DAC that impacts the core digital references in the DAC: reference clock, reference ground, and reference power.

    The impact may be direct, or it may be indirect through several intermediate components, over wires, or through the air. If you hear a difference with bit perfect audio streams, something is being transmitted to or induced in your DAC that is impacting the core digital references in the DAC (clock, ground, reference voltage), which in turn becomes audible when the signal gets converted to analog.

    As my digital chain has evolved from laptop to low power Raspberry Pi endpoints to special built devices like the Sonore microRendu to DIY NUCs with Audiolinux and Euphony to all sorts of power and USB and network and cable tweaks, I’ve stumbled into a high level strategy and hypothesis for digital optimization that has consistently pointed me in interesting (and usually better) directions:
    Invest in cabling, power, and digital hygiene to do as little harm as possible (directly or indirectly) to the DAC’s clock, ground plane, or reference voltage plane Invest in a digital endpoint that moves bit perfect digital data from ethernet to a USB DAC with as little timing variability and as much timing and signal integrity as possible (aka, as close to precision real time data streaming to DAC as possible)  
    For me, the key issue isn't so much latency, as it is reducing the variation in latency. By way of example, playback that has a latency of 1 second +- 0.00000000001 second would be preferable to a latency of 0.001 sec +- 0.0001 sec.

    For my current reference system, I am using an i7 NUC running AudioLinux in RAM as my Roon server, connected through an Uptone Audio EtherREGEN to a second i7 NUC running Euphony in RAM with HQPlayer as my endpoint, connected to my DAC by USB via a SOtM tX-USBultra special edition. As my system has evolved to this point (informed predominantly by the experiences of the extended community here at Audiophile Style, especially the legendary Novel thread, and the soon to be legendary DIY thread), here have been my experiences that are consistent with this “reducing variability in latency” hypothesis:
    By using a NUC with highly integrated Silicon on a Chip (SoC) design (vs laptop or regular computer), sound quality is better (the SoC results in better timing coherence and optimized signal paths between system components) By going with a stripped down in-memory linux OS with everything else disconnected and disabled in BIOS, sound quality is better (near real time OS) By configuring linux to give the highest real-time priority to the endpoint software (Roon Bridge or Squeezelite or HQPlayer), sound quality is better (more near real time) By configuring linux to give the highest real-time priority to the IRQ for the USB port (low level interface between the operating system and the physical USB port), sound quality is better (even more near real time) By removing the USB boot stick so the only thing on the USB bus is the DAC, sound quality is better (fewer IRQs for USB storage) By configuring the music server to bridge ethernet traffic to the NUC endpoint, sound quality is better (isolating ethernet traffic and interrupts) By increasing network buffer for Squeezelite or other end point software so that all ethernet traffic is front loaded and the current song and next song are loaded into memory within a second or so, sound quality is better (fewer ethernet interrupts during playback) By increasing the size of the memory buffer from Squeezelite or Roon or HQPlayer to the Linux ALSA driver, sound quality is better (less variability on feeding the USB driver) By having a higher powered NUC (quad core i7 vs dual core i5 Celeron), sound quality is better (able to be closer to real time since it has more horsepower) By configuring linux to dedicate a CPU core to the USB IRQ, sound quality is better (less contention with other processes) By configuring linux to dedicate a CPU core to the endpoint software, sound quality is better By using industrial-rated wide temperature RAM (presumably tighter tolerances parts, and better performance even at room temperature), sound quality is better By playing music stored on Optane storage on the PCIe bus (vs SATA or SSD), sound quality is better (more direct transfer path from storage to the CPU) By regenerating USB and/or ethernet signals, sound quality is better (signal integrity improvements)  
    None of these seem like they are RF noise related. These are all computer/OS/software configuration tweaks. What they all seem to share is the impact of reducing variability in the latency of the signal from the endpoint to the DAC and improving signal integrity, and thus (presumably) making the life of the PHY interface of the USB chipset a lot easier.

    Separately, any time I have mains isolated a digital component (batteries, super caps, etc), sound quality has improved. Any time I’ve inserted a better/faster power supply (Paul Hynes SR4, Uptone Audio LPS 1.2, LDPWR DXP supplies, etc) that delivers well-regulated voltage under very dynamic current loads, sound quality has improved. Similarly, better conductors and better shielding consistently improves sound quality, as does reducing mechanical vibrations on power supplies and digital components.

    I'm not drawing conclusions nor pointing at a core root cause. However, I'm finding that any change I make that is consistent with improving power (stability and speed), reducing RF, improving ground, and reducing variability in the latency of the digital signal seems to have a positive impact on sound quality.

    Interestingly, I have also experienced the inherent tradeoff between having a higher power system that is capable of delivering lower variations in latency, but having sound quality suffer from requiring more power (and the difficulty in keeping that higher power level stable and clean). My i7 NUC consistently sounded better than my i5 NUC, but sound quality suffered as I increased CPU speed. The better and more dynamically responsive the power supply that I used with my i7 NUC, the more I could push CPU speed (and the better things sounded) before sound quality peaked and started to suffer.

    So as I started looking for my next (final?) digital server, a core question for me was how powerful and near real time a digital server can one build, while still being able to deliver high quality power and not requiring additional noise generating components like fans? Can functions of music server and music end point be combined on a single powerful box (with more direct high performance connection between them) while also being clean enough to not adversely impact the signal output with power-related noise? How much control could I have over where processes were running and what system priority each was getting?

    As I researched DIY options to push the boundaries on my NUC servers, I began to hear whispers about a digital music server that was well beyond anything else available out there, and checks all the boxes I’ve come to find as important (and a whole lot more). The more I dug in, the more I realized that through the rabbit hole was a world of digital audio optimization that was WAY beyond what I was thinking was practical or doable, and that every detail somehow and some way still seemed to matter.

    In Part 2, I’ll dive into the guts (real and virtual) of the Extreme, and set the stage for  Part 3, where I share what I discovered in the world of Summit-Fi digital audio optimization.

    Equipment As Tested
    Digital Source – Review Setup

    Taiko Audio SGM Extreme with 8TB storage option ($27,000 as reviewed)
    HQPlayer Desktop ($235)
    Digital Source – Reference NUC Setup
    Stock Intel NUC7i7DNKE in standard case with 16GB consumer RAM and 32GB Optane stick ($800)
    Audiolinux ($120) and Roon Server ($120/year)
    NUC7i7DNKE motherboard in a fanless Akasa case with 4GB wide temperature industrial Apacer RAM and a 16GB Optane stick ($1,000)
    Euphony ($289) and HQPlayer Embedded ($235)
    PowerAdd Pilot 2 battery ($90)
    Stock Mac Mini file server ($500)
    DAC setup
    Chord DAVE ($13,000) – 2 channel
    For two channel for Chord DAVE, PCM+ mode, HF filter off, no crossfeed
    Chord Hugo TT2 ($5,500) – Headphone
    For headphones for Chord Hugo TT2, crossfeed set to 2
    Direct Two Channel Setup
    RCA direct to Voxativ 9.87’s with Voxativ 4D drivers ($50,000)
    Custom Furutech RCA to female banana adapters
    Custom Furutech XLR to female banana adapters
    Voxativ Ampeggio Speaker Cables ($4,000)
    Iconoclast SPTPC speaker cables ($2,500)
    Headphone setup
    Abyss AB-1266 Phi TC ($5,000)
    Sennheiser HD800 (with SR mod) ($800 used)
    Monoprice USB SlimRun optical USB extender cables ($150)
    Sablon Audio 2020 USB cable ($750)
    Uptone Audio USPCB ($35)
    Ghent Audio JSSG360 DC cables (various)

    SOtM tX-USBultra Special Edition ($1,300)
    Paul Hynes SR4-19 power supply ($500)

    AT&T fiber to the home, with Alcatel-Lucent G-010G-A ONT
    DXPWR DXP-1A5S single stage power supply ($109)
    PowerAdd Pilot Pro2 Battery ($90)
    Pace 5268ac Gateway/Router (AT&T supplied)
    Ubiquiti EdgeRouter 10X router/gateway ($109)
    DXPWR DXP-1A5DSC dual stage power supply ($159)
    PowerAdd Pilot Pro2 Battery ($90)
    Planet Technology MGB-TLX SFP transceivers ($30 each)
    Sonore opticalModule ($249)
    Uptone Audio LPS 1.2 power supply ($435)
    Uptone Audio EtherREGEN ($640)
    Uptone Audio LPS 1.2 power supply ($435)
    Monoprice and Cable Matters Cat 8 Cables ($10)
    Sablon Audio 2020 Panatela Reserva ethernet cable ($375, provide as demo)
    Sablon Audio router noise dongle (provided as demo)
    Vibration Control

    Daiza vibration Isolation platforms ($600)
    Custom precision rollerball isolators
    Music As Tested
    My Go-To demo tracks when demo’ing new pieces of equipment, and what I look for in each:
    Pink Noise (mono), from “The Ultimate Headphone Demonstration Disc” by David Chesky (Chesky, 24/192 FLAC) Yeah, its pink noise, but it tells you a lot about a set of headphones as you get oriented to your system. For 2 channel audio, I’ve found that pink noise is a great way to see if your speakers are aligned and you’re in the right spot. Great baseline reference to make sure things aren’t wonky and you’re in a good place (and it is sort of fun to think about all this technology being used to play a 24/192kHz noise file. Murakkaz Ah Ya Muddasin, from “The Splendour of Al Andalus” by Calamus (MA Recordings, DSD64) Remarkable recording in what sounds to be a majestic and spiritual centuries old cathedral in Spain. With the right equipment, you are transported to a place you’ve never been to but always want to get back to. When the full group joins in, it is profoundly challenging to reproduce the mids and highs without sounding shrill and congested. When the reproduction is effortless, it is magical (to say the least…my jaw drops every time when it’s “right”) If the sound chain is able to maintain that glorious soundstage, it is off the charts. Todd Garfinkle is a magician behind the microphone. Noche Maravillosa, from “Salterio” by Begonia Olavide (MA Recordings, 16/44.1 FLAC) Another gem of a recording and performance from Todd. The precision and clarity of the instruments (particularly the percussive ones) is intoxicating and tangible. Voglia Di Vita Uscir, from “Buenos Aires Madrigal” by La Chimera (MA Recordings, 16/44.1 FLAC) Todd also is a master at capturing performances in a more orchestral setting. These performances by La Chimera are a joy, and the sense of being there with the performers is absolutely intoxicating. Mahler: Symphony #2 'Resurrection’, 1st movement conducted by Iván Fischer (Channel Classics, DSD64) Mahler: Symphony #2 'Resurrection’, 5th movement conducted by Iván Fischer (Channel Classics, DSD64) Near perfect performance with a perfect recording. The dynamics and power of this performance are vivid and real: the orchestra virtually screams with one voice during the climaxes. This recording beautifully captures the essence of horns and low strings, which are very difficult to reproduce. The closest I’ve heard to the experience of the dynamics of a live orchestral performance. Rimsky-Korsakoff: Scheherazade, 1st movement conducted by Fritz Reiner (Analogue Productions Remaster, DSD64) The most perfect recording of the most perfect performance I’ve ever heard. Listening to this recording on a transparent system is a life changing experience: you are standing with Maestro Reiner in Chicago as his orchestra reaches for a performance for the ages. A cultural treasure, and worthy of building a world class system around. Organ Prelude, JS Bach Magnificat by Dunedin Consort (Linn, DSD64) Motet, JS Bach Magnificat by Dunedin Consort (Linn, DSD64) A breathtakingly lovely recording! The dynamics and harmonics of the organ can range from a muddy “eh” to “holy crap!” depending on the quality of the reproduction. Standing in the middle of the choir is a lovely test of imaging and voice reproduction: the more precise the soundstage the more you can pick out individuals (including depth and height…remarkable). Handel: Messiah - Chorus. O thou tellest good tidings by Dunedin Consort (Linn, DSD64) Handel: Messiah - Hallelujah by Dunedin Consort (Linn, SACD) A magnificent recording, reconstructing the original version of Handel’s Messiah, with a total of 12 singers. The normal complexity of the piece is captured in a way where you can hear each voice in the chorus, and how it comes together into a larger whole. An amazingly intimate performance when the reproduction chain can manage the complexity and dynamics and not have the soundstage become muddy and flat. Arnesen: Magnificat - Fecit potentiam by TrondheimSolistene (2l, 24/192 FLAC) This is such a lovely recording at any quality level, but goes from incredible to other worldly as the chain scales up. The orchestra, choir, and church should all have equal contribution to something far greater than the sum of its parts. When it all comes together, you can feel the three core elements feeding off each, creating a profound joy that sweeps you into euphoria. Stardust, from “Duets” by Rob Wasserman (16/44.1 lossless) Every track on this album is a gem, but this one is particular is a fantastic test of sound stage and imaging. At its best, you hear each backing voice precisely in space, but still presenting as a harmonious whole. In real life, detail and precision spatial placement isn’t hard and clinical, why should it be in reproduction? Oh, Lady Be Good, from “Plays Gershwin” by the Bassface Swing Trio (DSD64) Night and Day, from “Tribute to Cole Porter” by the Bassface Swing Trio (DSD64) These direct to disc Stockfisch recordings are extraordinary. Imaging and dynamics FTW. Recordings like these are why we obsess over the things we obsess about. I’m looking to get lost in the music, and the band appearing to be sitting right there. When tonal balance is just right, these performances just jump off the SACD. Shamas-Ud-Doha Bader-Ud-Doja, from “Shahen-Shah” by Nusrat Fateh Ali Khan (16/44.1 lossless) The first track from what was my surprise 2012 album of the year (see this video for the surprise ending). A remarkable supremely spiritual performance by a remarkable man, captured in an “eh” recording. The question for me when I’m evaluating new equipment is what it can do to elevate a middle of the road recording that is worthy of elevation. Let Me Touch You For Awhile, from “Live” by Alison Krauss (DSD64) I adore Alison Krauss. Having equipment that can reproduce the wonderful emotion and musicality of these amazing artists is why I spend so much time looking for the right speakers/cans/etc. Their Live album is special, and you can feel the humanity and emotion in this track. Fields of Gold, from “Nightbird” by Eva Cassidy (16/44.1 FLAC) An absolutely amazing and engaging performance, with a moderate recording and mics that were over driven. The dynamics of the performance unfortunately saturate the recording, and the breaks and near breaks can be painful in some chains. A wonderful song to listen to, but also a great song to see how much of the song is wonderful to listen to. Tenderly, from “While She Sleeps” by Art Lande (Blue Coast, 24/88.2 FLAC) Cookie Marenco has a gift for capturing piano, guitar, and voice as if you’re sitting in the room with the artist. If you’ve ever sat next to a wonderfully tuned piano with an extraordinary player, you know how magical that experience can be. The best pianos sing with resonances that envelop you. The best musicians know how to coax beauty and life out of the instrument. This recording from Art Lande captures that magic. The stronger the dynamics, soundstage, and precision of the system, the more lifelike this track becomes for me. I haven’t experienced this track topping out: the better the reproduction chain, the more lifelike it becomes. One World, from “Session 1” by Sareena Overwater (Blue Coast, DSD64) One World (Instrumental), from “Session 2” by Sareena Overwater (Blue Coast, DSD64) Real magic from Cookie. These tracks are wired directly to deeply held memories for me, and the stronger the reproduction chain, the stronger the emotion that they evoke. There are better examples of piano performance and better examples of vocals, but the emotional truth and power of this performance is unmatched. 99, from “Blue Coast Special Event 43” by Meghan Andrews (Blue Coast, 16/44.1 FLAC) Cookie knows how to record guitar too, and Meghan Andrews knows how to bring a performance that is worth catching in a bottle. Vous et Moi, from “Night and Day” by Willie Nelson (SurroundedBy Entertainment, 24/96 FLAC) What if Willie Nelson was in a dispute with his label, got pissed off, and invited the best musicians he knew to the studio to record an instrumental album in full surround? Yeah, this actually happened, and it is as awesome as you think it is. The album is amazing in a musical surround setup, but a proper 2 channel system puts you right in the middle of the band. Incredible stuff. Music in My Room, from “The Folkscene Collection, Vol. 3” by Cheryl Williams (Redhouse Records, 16/44.1 FLAC) We’ve all had the experience of being in a coffee shop or small venue, when someone with a guitar and something that has to be shared commands the attention of everyone in the room, and you have a moment where the whole room is one. These CDs where engineer Peter Cutler captured intimate in-studio performances at KPFK in Los Angeles are replete with those moments, but this performance by Cheryl Williams stands out for me. With a great reproduction chain, the guitar is real and present, and the voice and singer connect at a deep emotional level. A jewel of a moment, waiting for the right equipment to be a moment again. All I Want, from “After Blue” by Tierney Sutton (BFM Jazz, 16/44.1 FLAC) Tierney Sutton has a striking clear and present vocal style, and that is on full display on her “After Blue” album of Joni Mitchell standards. I continue to be amazed how ever better DACs extract ever more nuance and subtlety of performance from top tier vocalists. It is a joy to hear the depth of craft and art of vocal performance on tracks like this. Rosa fresca, from “Il viaggio d’amore” by Arianna Savall and Petter Udland Johansen (Carpe Diem, 16/44.1 TIDAL Lossless) “The journey of love” is a marvelous exploration of love through the ages, from multiple cultures and times. The whole album is a joyous wonder, but the opening track (“Fresh Rose”) of a traditional song from the 1500s is an invitation to join in joy and unbounded hope. The company of players is feeling it, and you do too. When you’re hearing every string pluck in the strums and the voices come together into something much larger than the sum of its parts, you’ll be glad you accepted that invitation. L’Amor, from “Bella Terra” by Arianno Savall (Alia Vox, 16/44.1 FLAC) If Rosa fresca makes you fall in love with Arianna Savall singing about love, you’ll want to seek out her “Bella Terra” album. An accomplished harpist and vocalist, Savall is at her best when she brings both together: voice and instrument are one, and evoke marvelous sound and emotional resonances in each other. Traveler, from “Little Crimes” by Melissa Menago (Chesky, Binaural 24/192 FLAC) Airplane, from “Little Crimes” by Melissa Menago (Chesky, Binaural 24/192 FLAC) A gem of a recording from Chesky: direct binaural recording, made in a church while it is raining outside. Like all Chesky binaural recordings, you are there sitting with the performers (Airplane), with special magic from the sound of the rain outside of the church (Traveler). Fantastic test of soundstage and spatial detail. Hold On, from “Sessions from the 17th Ward” by Amber Rubarth (Chesky, Binaural 24/192 FLAC) Don’t You, from “Sessions from the 17th Ward” by Amber Rubarth (Chesky, Binaural 24/192 FLAC) More Chesky magic. No rain this time, but Amber’s rich voice + violin + guitar + percussion are amazing on any system, but the sense of being there scales beautifully as the reproduction chain improves (it is magical when your system crosses some threshold of transparency…all of a sudden you are there). Stuck In A Moment You Can’t Get Out Of, from “Open Your Ears” by The Persuasions  (Chesky, Binaural 24/96 FLAC) One last gem from Chesky. There is a profound difference to listening to a recording of a group of people sing, and being with a group of people that are singing. This is another recording that (at least for me), when you cross some magical threshold of transparency, the people become real. Ephemera, from “Ephemera” by Carla Lother (Chesky, 16/44.1 FLAC) A stunning interpretation of an incredible poem by William Butler Yeats. The recording is exquisite, but the incredible sense of space and balance amongst the performers is very fragile. The better the chain, the more perfect the recording becomes. Karamawari, from “Gamushara” by YAMATO the drummers (TIDAL MP3) Drums are notoriously difficult to reproduce in the way you experience them in person. There is a physicality that is lost in most systems. Hearing a group of percussion masters really bring it on a system that can approximate that in person experience? Amazing. Get Lucky, from “Random Access Memories” by Daft Punk (24/88.2 FLAC) Another track that transcends pop when played back through equipment that really reproduces the full range and dynamics of the recording. The subtlety and layers on Nile Rodgers’ guitar work is incredible, and the recording is outstanding so you should be able to hear it all. I listen for whether it is washed out, and how well I hear all the (considerable) nuances in his playing. Take Five, from “Time Out” by Dave Brubeck (Analogue Productions SACD) An excellent test of dynamics at the high end. As an aside, these Analogue Productions remasters are off the charts! No Love Dying, from “Liquid Spirit” by Gregory Porter (24/192 flac) Another lovely recording and performance, that on a balanced system hits a resonance that is next level for me (just sounds “right” and get the “wow!”) When things are not in balance or boomy/shrill, I hear it loud and clear. Beethoven: Symphony #9, 4th movement by Suitner (OG Denon, 16/44.1 lossless) This was the first CD I ever bought in 1984 (first CD ever made?) I know every second of this movement and every nuance. My current 2 channel setup was the first time I had ever heard the entire movement without a break (every other system I’d ever had/auditioned had some break at some challenging passage). So What, from “Kind of Blue” by Miles Davis (Japanese single layer SACD version) One of the finest recordings and performances of the 20th century. Always the last track I play during any audition. Until there is a time machine to take me back to March 2 and April 22 1959, I will buy every new remaster of this album, and play it on every piece of high end audio kit I can find.  
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  5. Upvote
    Gavin1977 reacted to bobfa for an article, RCA Victrola 711V3 2020 | His Master's Voice Reimagined   
    RCA Victrola 711V3

    As a child, when we visited my grandmother's house, there was this radio console along the wall of her living room. I wish I had a picture of that room; my memory is a bit fuzzy. Fast forward a decade or more, my grandmother became too ill to stay in her home and that console ended up in the basement of my father's home. There it sat for another eternity!  I finally took the console home. To this day, I do not remember why I took it. It is terribly heavy.  We used it as a Dining Room side table.
    Fast forward to about 2017, I was getting fed up with the TV cabinet in our Living Room. While it was a nice piece of furniture, it was HUGE and there was no TV.
    Below is a picture from 2016 when I was reworking the gear inside. Back then, the MacMini was playing Audirvana. I used Rotel separates into B&W Matrix 805's. The speaker cables were Transparent Audio 14 ga cable. The interconnect cables were old Interlink Reference A. The network was WiFi, and the USB cables were generic. The DAC was an Arcam rDAC. There was an older Monster Cable power system. The remote control was Apple Remote Desktop from a MacBook Air.
    This system sounded so much better than two Sonos Play Five's sitting on top of the cabinet! Since then, I have upgraded everything and not in the sense of the Cybermen.

    One of the first problems was to "steal" the side table from the Dining Room. Once that was agreed upon, progress slowly started. Here are some pictures from 2018 of the console before I started.    

    There was a flurry of ideas in my head. First, I would keep the record storage section in place. It is not big, but it is convenient! The second was to take the section next to the records and put the main electronics in there. Next is the turntable. I HAD to find a "really good" turntable to put where the old 78 record player was. It was not until the Axpnoa 2019 show that I found what I thought was right. Progress has been slow until 2020.  
    It took three years of this one idea rattling around in my head of what to put in the pull-down door radio section!  I think I have found an interesting "Replacement Tuner.”
    When I started this project, I did not expect to be sidetracked by my DIY self. I took down the old TV cabinet and stripped out the Victrola about ten months ago.  I have been building, buying, testing, researching, and listening to digital gear for over two years, But:
    Goldilocks had not arrived yet.  
    So here I am with this beautiful cabinet, and I was trying to fit in the stack of modern electronics. Things just did not hit me right yet. There was still this harshness in the upper-frequency ranges. I resigned myself to keeping the server in the basement.   I used the Sonore OpticalModule and the SoTM tx-USB Ultra for cleanup. Two Euphony licenses and the music on a NAS. I found my highpoint in music sound quality.  
    During recent weeks I reviewed the JPLAY FEMTO Software and JCAT USB and NET FEMTO cards.  That review was a turning point for me, I had some corrections in thinking to make.  I realized that while all of this work had increased my learning and incrementally improved the sound quality, I was not satisfied. My wife still asks me to put something on the stereo at dinner time. I had not met my original goal of simplifying the system so anyone can use it or compacted the hardware down to fit into the Victrola. Gear is spread all over the house.
    I decided that I was going to fix this problem. The stereo would all fit into the cabinet, and that was that.   
    Back to the drawing board!
    The first thing was to tackle was the turntable. I had saved the roll out base from the old 78 rpm record player. I went back to the turntable I had targeted before, and sure enough, it was going to fit.    
    The Rega Planar 8
    I have not finalized the base for the Planar 8; I am using three layers of Oak Flooring material. I bonded it together and cut it to fit into the opening in the rolling tray. I know that this a compromise. I am looking at Butcher Block Acoustics maple blocks. I may get a 3in thick one and mill it to fit into the opening.

    Getting the wiring from the turntable to the phono stage and power took some thought and planning. The cables have to move as the table rolls in and out. I removed the rear of the cabinet and cut a slot to fit the cables at the top of the side panel. Now the cables cleanly move and will not get damaged.
    Here is a little preview of where the cables go.  

      The Planar 8 fits perfectly in the space I have available with its dust cover.

    Enter the Digital Music portion of my project.
    Wow, where to start. I am going to summarize a bit here for clarity. In the last four years, I have tested many designs. 
    A co-located MacMini with the UpTone Audio modifications Two models of Sonic Transporters. The SoTM trifecta. Almost every Rendu, including the SE Optical one  I have built my own DIY Xeon Server, put an Intel NUC into a case.  
    I have tried
    Multiple power supplies Apacer industrial RAM Intel Optane SSD. Windows, macOS, AudioLinux, Sonic Orbiter, Gentoo Player and Euphony OS. Multiple networking systems Countless cables  
    All of my listening, research, construction, and wand-waving have led me to the conclusion that I cannot build my way up to what I want. So research time. Internet, Magazine archives, phone calls, emails, listening sessions.
    Here are my criteria:
    Run Roon Be #VictrolaFi or even better #KallaxFi RIP CDs Dual box, as I have proven to myself, it works the best. BRIDGING! Other outputs than USB, just in case User-supplied and upgradeable internal storage Wired networking Great Power Supplies  Proven track record. No user-managed OS (leaves out macOS and Windows) It goes without saying whatever I do had darn well sound a lot better than what I have now.   
    I could go over the last year of background work, but that might be boring. I ordered a full set of Antipodes Audio gear: CX, EX, P1, and P2, all of which have arrived for listening. I am delighted with the Antipodes Audio equipment.  They fit perfectly in the Victrola. I added a shelf to separate the two servers for airflow and mechanical isolation. The CX is running Roon Core and has the P1 ripper platform under it. The EX is the Roon Bridge Output and has the P2 DDC under it. Note that the platforms also act as vibration damping.
    And it all fits nicely in the old amplifier and speaker compartment #VictrolaFi. Or your favorite IKEA Kallax unit!  #KallaxFi

    AM/FM/SW replaced by Roon Live Radio 

    It took me a very long time to get this quadrant of the cabinet in order. 
    I have placed the NEO power supply for the Planar 8 and the Musical Fidelity Phono stage here. There is room on the shelf for turntable accessories. The stereo has a dedicated 12.9in iPad as the Roon Remote and more.
    The existing door did not open all the way.  I had to remove framing that was around the radio and the lever arm that held it up. I replaced the lever arm with a modern soft door opener that lets the door open 90 degrees.  

    I mounted an iPad holder to the drop-down door.  I locked the rotation on the iPad so it  does not turn upside down when you close the door.  The Apple keyboard cover stores inside the cabinet along with the Apple Remote for the Kii Control and an Apple Pencil.  I am waiting for an iPad magnet mount which I think will work better.

     Just one more thing (and it does not fit in the cabinet)
    I replaced all of the AC equipment with a Puritan Audio Laboratories PSM158 Master Purifier and six "Mains Cables." Four cables for the Kii Three System and one each for the Antipodes CX, EX servers. While this has only been with me for a short while, it is head and shoulders above my previous AC protection only equipment. It was amazing when I added the second set of power cords for the Kii Three + BXT speakers.
    There are two compromises right now. The AC power for the turntable and the phono stage do not go through the PSM158. The second compromise is that it does not fit in the cabinet because I have records in the fourth quadrant of the Victrola.

    Loose ends
    There are always little things that I have not covered. The first item is the Puritan Audio Laboratories, Ground Master; it is a little box that connects the system to a separate outside earth ground. It is NOT an AC line ground or safety ground. The job of the Ground Master is to "drain off" electrical noise. I have it all installed, but I still have to do the testing with and without it to see what I can hear.   

    The next loose end is that I cannot help my self but to try to isolate the ethernet from the rest of the house network. To that end, I have a Sonore opticalModule feeding the CX. The fiber cable then goes directly to my Ubiquity Switch.
    There are two battery-powered lights inside of the cabinet to help with lighting.
    Now just to add to the controversy of this "build!" During the tenure of both of my closed cabinets, there has been a heat problem. A few months ago, I did some research and found a Silent PC ventilation fan. The Noctua NF-A14 ULN fan makes no noise. It is a fixed speed 12volt fan, so there is no PWM modulator to make electrical noise. I mounted the fan at the top rear of the electronics side of the cabinet, and it exhausts outward. When I had the Xeon server the HDPLEX 400 power supply inside of this tiny Victrola box, it worked perfectly. So it stays!

    There are Hue lights behind the speakers and the Victrola for ambiance.  There are five SMPS supplies behind the cabinet.  Still, this leaves a mess of cabling. I could never see using an open rack in a family living situation. Neither can my wife! 

    Some final words
    Slideshow and Photo Album on Flickr
    Victrola Re-imagined |  Victrola Photo Album
    This is the culmination of about three years of thinking and work. It is almost scary to think I am done!   I just had two people over for an afternoon listening session. They both commented emphatically that the sound of the system is a lot better.  They seem to disagree on why.  I say it is the sum of all parts!
    Does this project end my DIY experimenting? I have graduated from the Command Line and Screwdriver undergraduate program. But, remember that I am an experimenter at heart. 
    Oh, there is the A/B with and without the Sonore opticalModule. Wait, I have not listened with and without the Ground Master.
    And yes, I still have to review the Allo Digione Signature. At least now I have something to compare.
    Note that I do Audio Systems Design Consulting and I sell some brands of equipment.  Please review my profile for that information.
    Now to setup profiles for my Wife and Son in Roon!  
    Another Little Black Box
    Welcome to the Victrola Blind Audition

    One of the ongoing themes in my system designs is to make things simpler for everyone in the house.  The Kii Three’s are pretty simple.  Add Music Servers, Turntables, and the like then folks need training.  
    But what if you could, “Just ask Siri?” 
    By accident, I found “Another Little Black Box.” This box gives me voice control via Siri using Apple HomeKit. It is Airplay 2 compatible, and there is an App for your devices that can play local music files from the network and connect to services from virtually any service you can name. 
    If you live in Google Land or the Amazon World, it works there too! 
    Here are some of the services you can access (video): https://flic.kr/p/2iApTYF
    There is no software to install or manage on the device.  There are no controls on the device used during the operation.  
    The black box needs a network connection wired or wireless, or its unique wireless network. It can output VIA single-ended analog or Coax Digital, which I am using to feed the Kii Control.  There is also an analog input.
    Initial setup is reasonably straightforward; download app, run it, follow directions.  
    How does it sound? To my ears, it is reasonably pleasant. Better than that Amazon Echo Link I tried last year.  This device is about the simple operation, broad-brush access to multiple services, and family involvement. Win, Win, Win!
    Now switch inputs to the Antipodes CX+EX Roon server, and you hear a HUGE difference.  But Roon does not know Siri, Bandcamp, IDAGIO, or Spotify! 
    One more hint.  The company got yelled at by the Internet when they wanted to stop the support of some older hardware.  
    Have I given you enough clues?
    The Little Black Box is the:  

    At $449 the SONOS Port is a very enjoyable addition to the system.  We are just starting to bring it into the fold. The only downside is that you have to ensure that the Kii Control is set to the Coax input when they shut down so that when you ask Siri, they wake up!
    System Video 

    Equipment List
    Victrola 711V3 Cabinet 
    Kii Three Speakers, Kii Control and BXT modules
    Antipodes CX Server with 4tb of Samsung SSD 
    Antipodes P1 Ripper connected to the CX
    Antipodes EX Server 
    Antipodes P2 DDC for the EX as needed
    Sonos Port
    Rega Planar 9 Turntable with Ania cartridge
    Musical Fidelity MX-Vynl Phono Stage
    12.9in iPad Pro
    Sonore opticalModule
    Sonore/SGC 5v Linear Power Supply
    Cable Matters Cat 8 Jumper
    Transparent Cable High Performance USB (for EX to P2)
    Transparent Cable Ethernet (between CX and EX)
    Moon Audio Silver Dragon USB cable for the Kii Control
    Mogamai Balanced cables from Phono Stage to Kii Three
    Mogamai 3080 AES/EBU cable
    Puritan Audio Laboratories
    PSM158 Master Purifier
    Six Mains Cables
    Ground Master
    Roon Labs Core on CX and Roon Ready on EX
    Resilio Sync to keep CX and NAS in sync
    Sonos App as needed
    Noctua NF-A14 ULN fan
  6. Thanks
    Gavin1977 reacted to austinpop for an article, UpTone Audio EtherREGEN Review and Comparison   
    UpTone Audio EtherREGEN Review and Comparison
    Rajiv Arora
    The UpTone Audio EtherREGEN (shortened to eR for the rest of this review) is a diminutive Ethernet switch with a bold value proposition. UpTone claims it “...is capable of producing surprisingly audible sonic improvements in fine music systems.”  In this review, I’ll evaluate this claim of sonic improvements, and pit the eR against a couple of competing “audiophile” switches. But first, some background.
    For many, the very idea that an Ethernet switch can make a difference in sound quality (SQ) is anathema. “Where’s the proof,” they cry. “Show me the measurements.” At an even more fundamental level, their question is: “How could it make a difference?” An Ethernet switch’s job is simply to link Ethernet devices together by relaying Ethernet frames between the devices connected to the switch. As long as it does this without error, how could it affect SQ? After all, audio components that use Ethernet - servers, streamers, DACs, etc. - typically buffer the network data stream before further processing. As long as the data arrives correctly - bit-perfectly - how could SQ be affected?
    As someone with both an academic and industry background in networking, I can sympathize with this skepticism. Not that many years ago, I too scoffed at the notion that any part of the chain of digital components upstream of a DAC - not just switches - could have any impact on SQ. It was only when I actually took the plunge and started listening to gear that I realized the upstream chain could profoundly affect - both positively or negatively - the SQ of the system. On the networking side, this  includes switches, routers, and even Ethernet cables, which I admit I found very disconcerting. I did my own experiments using OS monitoring tools to look for errors, retransmissions, or any other indications of functional misbehavior, and found none. All I could conclude was that we were hearing some orthogonal phenomenon - unrelated to the actual digital function of the device - which was not yet understood.
    My first foray into the world of audiophile switches was almost three years ago. An Audiophile Style forum member, whose ears I trust, posted about the improvements he heard after getting his chain modded  by Korean manufacturer SOtM, to use their then-new sCLK-EX clock board. Based on his enthusiastic report, I took the plunge and had my gear modified as well. This was the famous SOtM trifecta - a modded switch, a modded sMS-200 endpoint, and a tX-USBultra USB regenerator. The clock board in the tX-USBultra regenerator provided the system (25MHz), USB (24MHz), and Ethernet (25MHz) clocks for the entire chain. I posted about my impressions here, here, and here. Quoting myself: While we expected the tX to have an impact, we were just astounded by the effect of the switch.
    So while I have experienced the SQ impact of a switch, I do still wonder: how does a switch impact SQ? To be fair to the skeptics, manufacturers have not really answered this question. The first wave of products, like Paul Pang’s modded switches, the SOtM-modded switches, and The Linear Solution OCXO switch, were all consumer switches that had been modded to:
    Replace some components with better quality, such as capacitors and regulators Replace the ultra-cheap Ethernet clock (typically 25MHz) oscillator with a TCXO or OCXO oscillator, or modify the board to accept an external clock Allow operation with high-quality external linear power supplies.  
    All of these modifications were found to dramatically improve SQ to a varying degree, which was enough for many audiophiles like myself to adopt them, and for manufacturers to offer them. But in terms of an actual explanation of the mechanisms at work, manufacturers offered only vague statements about reduced noise generation, resistance to RFI/EMI, and lower clock phase noise.
    Technology Background
    To his credit, UpTone’s design engineer, John Swenson provides more than just generic correlation evidence to support the rationale and design of the eR. In a white paper entitled Understanding how perturbations on digital signals can affect sound quality without changing bits, and how these issues are addressed by the UpTone EtherREGEN, Swenson enumerates the mechanisms that degrade SQ, and how the eR addresses them. I look forward to the measurements data to back up the claims, which Swenson says he will publish soon. I encourage all of you who are interested to read the white paper at the link above.
    The claims are certainly intriguing. While the phenomenon of leakage currents is something Swenson has written about extensively on this forum, what I found particularly intriguing was the claim that the high phase noise of a low-quality upstream clock induces ground plane noise on the downstream device’s receiver circuits. This ground plane noise in turn induces additional jitter (i.e. adds to the phase noise) on this device’s clock. He claims this effect is additive, so phase noise continues to degrade as data moves down the chain. The rubber hits the road when the receiving device is the DAC. This is where the accumulation of induced jitter has a sonic impact on SQ.
    Is this proof? Certainly not until Swenson’s measurements are published, and even then I am sure there will be a robust debate about these theories! I find these claims intriguing because they do correlate with my empirical findings:
    The sonic effects of switches etc. are not related to their functional correctness. Sonic improvements accrue by replacing SMPSes with linear PSUs, and grow with increasing LPSU quality. Sonic improvements accrue by improving the system clocks of all upstream devices, and SQ improves as clock phase noise is lowered.  
    How does the eR address these SQ-sapping gremlins? Swenson describes a multi-pronged approach:
    Use special high-speed digital isolators to block leakage currents, Use fully differential circuitry to block upstream phase noise, and Reclock outgoing data with an ultra-low jitter local clock.  
    For more details, I refer readers to the white paper.
    Product Summary
    Like any Ethernet switch, the eR has multiple ports, and provides connectivity between devices connected to these ports. The interesting aspects of the eR are:
    It has 4 x RJ-45 gigabit ports and one gigabit SFP (Small Form-factor Pluggable) cage (typically to accommodate optical transceivers) on the ‘A’ side of the unit On the ‘B’ side is a single RJ-45 100Mbps port The ‘A’ and ‘B’ side are separated by a so-called Active Differential Isolation Moat (ADIM™) UpTone claims the best SQ occurs when the DAC-attached machine and the upstream network are on opposite sides of the ADIM™ No direction is preferred, and SQ benefits are claimed to be identical whether going ‘A’ to ‘B’ or vice versa. The eR supports an external 10MHz reference clock on its BNC input. When connected, there is a slider switch to select this mode of operation. External power supplies are supported in the range 7-12V DC, with current requirements of 7V/1.4A, 9V/1.0A, 12V/0.8A. Finally, a ground screw is provided.  
    Key Questions
    I always find it useful - both for myself and the  reader - to lay out the key questions that my review is trying to answer. Proceeding from that, I then develop an evaluation plan, or testing strategy, to answer these questions. 
    The key questions with the EtherREGEN are:
    Does it work? Does its presence in the chain deliver an improvement in SQ? How does SQ scale (improve) with power supply units (PSUs) of increasing quality? Does SQ improve with an external 10MHz reference clock? Is SQ better when crossing the ADIM™ moat: A <-> B? How much of this is due to the B side being 100Mbps? Does grounding the eR improve SQ? Does fiber sound better than copper? Does SQ vary with optical transceivers and do attenuators help? How does the eR compare with other audiophile switches? Is the moat impregnable? Are upstream or downstream improvements no longer necessary? What happens when you go down the rabbithole of chaining switches?  
    Review System Topology
    To aid the reader’s understanding of the various configurations tested in this review - which can quickly become confusing with all the possible combinations  - I’ve shown below a pictorial representation of the audio systems I used in my review. 
    Primary System
    As I described, when it comes to audiophile switches, this isn’t my first rodeo. In fact, my current system employs a chain of two such switches in series - the TLS (The Linear Solution) OCXO and the SOtM NH-10G switches.
    I’d like to call the reader’s attention to the fact that my system uses an all-in-one music computer. This is a topology choice, just like others use separate computers to run the music server software and the endpoint/renderer. There are pros and cons around these topologies, which are not relevant to this review. The key point to note is that UpTone recommend the eR go immediately upstream of the DAC-attached machine. In my case, this is the music computer.

    For this review of the eR, I held the rest of the topology constant, while varying the network connectivity in the grey box as shown.

    Music Data Flow
    In my system, music data resides on my NAS. This is a choice I’ve made. Many users will have music reside on a storage device (SSD, HDD etc.) on the music computer. My choice of NAS implies that during music playback, data flows across the switch, regardless of whether I am streaming local files, or from Qobuz or other streaming services.
    Second system
    I always like to test in multiple systems, so I also evaluated the eR in my friend M’s system. M recently sought my advice to adapt his home theater setup to enable high-quality 2-channel listening. He’s been on, and very happy with, the topology below for a few months, and was curious to hear how the eR would fare in his system. M doesn’t have any special power conditioning, and uses stock or entry-level cables across the system, except where shown. His music lives on his NAS, and he uses DLNA to stream from minimServer on the NAS directly to the DLNA renderer in his iFi Pro iDSD DAC.

    Function and Operation
    There isn’t much to say about the eR functionally. It’s an Ethernet switch. It works. 
    Here are some operational considerations:
    Heat: The case does run hot. In my setup, in a well-ventilated spot, with a single fiber input on the A side and the B side connected to my music computer, the unit was at 44ºC. This isn’t a problem, but adequate ventilation would be a consideration when placing the eR. Stability: Due to its diminutive size, the eR can be lifted off its feet by the torque from heavy cables, as I found with the SOtM dCBL-Cat7 Ethernet and dCBL-BNC-75 clock cables I was using. To some extent, you can mitigate this by using the same cables on both the A and B side, or consider a weight of some kind that doesn’t impede heat dissipation. 100Mbps: Assuming you cross the ADIM, as UpTone recommends, you’re limited to a throughput of 100Mbps. This isn’t an issue while streaming music, but it does increase the time for some operations. In my case, the DAC-attached machine is a music computer running Euphony OS (a variant of Linux) and the Stylus music playback software. Here are the operations where you notice the 100Mbps limit: OS updates take significantly longer than with a Gb switch. Obviously, this is moot if your ISP plan is less than 100Mbps. Mine is 300Mbps, so I did notice. Of course, I could temporarily move the connection from the B to the A side of the switch, but that’s inconvenient. Stylus has a “Buffer queue to RAM” feature that results in a notable SQ improvement. However, if buffering a whole album, especially at higher resolutions like DSD and DXD, this operation can consume several minutes at 100Mbps. Here again, this depends on your setup. If the music is on local storage, then this is not an issue. In my case, the music is stored on an external NAS, so music file I/O flows through the switch and incurs this limit.  
    With all that said, these operational considerations were minor and did not detract from the sonic performance of the eR. 
    Review Playlist
    EtherREGEN Review Playlist on Qobuz (US)
    To enable you to listen to the same tracks that I did, I have created a public playlist on Qobuz USA. This playlist includes the tracks mentioned in this review, as well as some of the others I listened to in the course of this evaluation. Please note that in some cases, the Qobuz track will only stream at 16/44.1, whereas I may have used a local hi-res version. Still, this gives you a sense for the music I listened to for evaluation.
    Listening Impressions
    I’ve made it a habit to burn in review gear for a minimum of 200 hours before even attempting to evaluate its sound quality. In the case of the eR, I was very glad I did, because it most definitely needs burn-in. The bulk of the change happens in the first 24-48 hours, but my unit continued to improve for several more days.
    Speaker-based Listening
    Since my system is already tricked out with existing switches and high-quality power supplies, I’ll first describe the eR in M’s system, which is much more “typical!” We baselined our listening with no switch in the path - just a direct generic Ethernet cable from his router to his Pro iDSD DAC. Refer to the system topology shown earlier.
    Bowspirit, from Austin instrumental ensemble Balmorhea’s excellent album Constellations (Western Vinyl, 16/44.1), is also the opening theme of the quirky indie show, Rectify. It’s a richly layered track with violins, banjo, acoustic guitar, and drums, that defies pigeonholing into a genre.
    Step 1: Add eR with stock SMPS into the chain. Router on ‘A,’ DAC on ‘B’
    Since I’ve heard this kind of effect before, I was watching for M’s reaction, and he didn’t disappoint. “What just happened,” he exclaimed! There was a big increase in the soundstage size, especially in the image depth. The violins and the banjo were more precisely positioned, and there was more texture and detail all around.
    Step 2: Replace stock SMPS with Farad Super 3 LPS
    This was another significant step up in SQ. Not only was the bass deeper, but it became much tighter and well-articulated. The wallops of the drum went from somewhat woolly thumps to emphatic thwacks. The violin and banjo lost their slight stridency and sounded more tonally refined. Both image size and fine details went up a couple of notches.
    Step 3: Externally supply a 10MHz reference clock with the Mutec Ref-10 
    M already had a Ref-10 in his system, providing a reference clock to his iFi Pro iDSD DAC. So it was a simple matter to use another clock output to reference-clock the eR. Despite the already impressive SQ gains from steps 1 and 2, this was yet another big uptick in SQ. This step was all about palpability and realism. The effect of the ultra-low phase-noise reference clock  is akin to swapping in a superior lens in a camera. Everything in the soundstage snaps into greater focus. Instruments take on a 3-dimensional realism, instrument placement in the image is even more precise.
    All together now…
    In a subsequent session, we swapped periodically between the baseline (no switch) and the full monty of switch+LPS+clock. 
    This time we listened to a delightfully fresh interpretation of Carmina Burana, by Anima Eterna Brugge/Jos van Immerseel (Zig-Zag Territoires, 24/96), played with a smaller ensemble on 1930’s instruments. The difference between no switch and the full monty was both stark and startling. On In taberna quando sumus, the full monty switch configuration opened up the soundstage dramatically. The individual sections of the chorus were more precise, with more depth. Individual voices in the chorus were easier to distinguish. Brass instruments - trumpets, trombones, and tuba - in particular were much more realistic, with more texture and air volume.
    M texted me later that evening to say he had placed an order for the eR.
    Headphone Listening on my Primary System

    Please note that the switch configurations shown in this and subsequent sections fit into my overall system topology (shown earlier) by replacing the grey box pictured on the left.
    For the first round of tests, I listened to The Mandalorian Theme - Epic Version by L’Orchestra Cinematique (HM Chapel Music, 16/44.1). While I wasn’t at all impressed by the series, this epic theme makes for a great demo track. 
    Since I was impatient, I compared the “no switch” configuration to the full monty. The two configurations are pictured below. 
    Even in the “no switch” configuration, the system sounded great, with satisfyingly deep bass in the opening notes, and great air and dynamics on the triumphal trumpet theme. But with the full monty configuration, there was just so much more! The image size was now huge, and the bass was deeper and fuller. On the drum beats, you could effortlessly distinguish the different percussion instruments collectively being struck. Perhaps because my system is much more resolving, and because I was using an even better PSU and cables, this difference between no-switch and full-monty was much greater on my system than it had been on M’s system.
    I observed a similar difference whilst listening to this excellent new release of Beethoven Symphonies 5 & 7 by Andrew Manze, NDR Radiophilharmonie (Pentatone, 24/96). On the second Allegretto movement of symphony no. 7, the ambience and tension, as this movement builds from a pianissimo exposition of the strings to the crescendo with the full orchestra, is much more palpable with the full-monty switch configuration. The soundstage is larger, the strings have more dimension and texture, and the tympani strokes are fuller, deeper, and again, more textured.
    This was a very promising start. Even before the head-to-head comparisons, the eR seemed every bit as capable as my previous switches in delivering a big boost in SQ. 
    I next explored how the eR scaled with PSUs and an external clock, and how SQ varied in different operational modes. My aim was to tune SQ to the best achievable, before getting into comparisons.
    Comparison of PSUs
    SInce I had already tested the stock SMPS in M’s system, I omitted it from this comparison. I gathered up all the PSUs I had available, and did a little shootout. The switch configuration was the same full-monty setup as before, as shown in the diagram on the left. I then varied the PSUs, with all of them set at 12V.
    There were indeed big differences between PSUs. As the PSUs got better, the SQ improved along the expected lines: deeper tighter bass, better air and separation, bigger soundstage, and smoother tonality.
    Cutting to the chase, here are the PSUs in increasing order of SQ. All of them are a big step up from the stock SMPS.
    A. SOtM sPS-500 with 7N UPOCC silver DC cable

    Even though technically an SMPS, the sPS-500 did sound significantly better than the stock SMPS, thanks presumably to the noise cancellation and filtration that is SOtM’s forte. The SQ was remarkably clean and smooth, with good clarity and resolution. However, it did sound smaller and more closed-in compared to the rest of the field.
    B. Farad Super 3 with Audio Sensibility Signature Silver DC cable

    The Farad delivered an even blacker background, with a more expansive soundstage. There was more density and texture, and it did wonders to the bass. This PSU really allowed the eR to shine, and showed you what it’s capable of.
    C. Paul Hynes SR-4 with Paul’s DC3FSXLR silver cable

    As I’ve found in other shootouts, the SR-4 and the Farad are very comparable in SQ. In this particular comparison, the SR-4 won out by a slight margin due to its slightly larger soundstage. Transients also seemed just a bit more well defined. Both the Farad and SR-4 are excellent companion PSUs to the eR!
    D. Paul Hynes SR-7 SR (single regulation) with Paul’s DC6FSXLR silver cable

    These last 2 PSUs fall into the category of overkill, since they are substantially more expensive than the eR, and less likely to be chosen as companions for the eR. Although certainly, for someone who already has a unit (like me) with an unused rail, this would be an excellent option.

    First up was the “standard” Paul Hynes SR-7, which has just the single custom regulation stage. Good as the SR-4 and Farad were, the SR-7 SR raised the SQ of the eR even further. This is as much a compliment to the eR as it is the SR-7, as it takes two to tango, and a component’s design has to be of sufficient quality to even benefit from a PSU of this caliber.

    With the SR7 SR, the bass got even tighter and deeper, and the music took on a pleasing increase in density and solidity.
    E. Paul Hynes SR-7 DR (dual regulation) with Paul’s DC6FSXL silver cable

    It never ceases to amaze me how much the addition of a second regulation stage to the  already-excellent SR-7 improves SQ. Yet it does, and the eR rewards you for providing it. The SR-7 DR (dual regulation) rail seemed to reveal another layer of hidden detail, while further enhancing the bass, articulation, and soundstage. If there is a better external PSU than the SR-7 DR, I dearly want to hear it in my system.

    As it stands, the eR improved with every stepwise increase in PSU quality all the way to the best in my stable. Very impressive indeed.
    Effect of Ref-10 reference clock
    Since I’ve already described the effect on M’s system, I’ll only add that I observed an even bigger jump in mine. I described it as a lens snapping into focus, and the same analogy held here. On the Beethoven 7th, in the pianissimo exposition, the individual violas and cellos in the string sections became discernible, and in the crescendo, when the wind instruments kick in, here again, it was much easier to distinguish the french horn from the trumpets.
    SQ difference due to ADIM™
    Was there an SQ difference if the music computer in my system was connected to another port on the A side, vs. connected to the B side, where data would cross the ADIM™ isolation moat? Yes there was. While the A side connection still gave a sonic benefit, there was an additional boost when crossing the moat. This SQ boost manifested as an increased calmness, a lowering of fatigue, and a smoother tonality, while retaining the clarity and resolution.
    But could this just be the difference between 100Mbps and 1Gbps speeds? To test this, I used the Euphony OS advanced settings on my music computer to force the JCAT Net Card port to a speed of 100Mbps. Would I achieve the same improvement in this case, by using the A side of eR, but forcing the port down to 100Mbps? In a word, no. I heard very little difference when the port was connected to the A side, whether it was auto negotiating to 1Gbps, or when speed was set to 100Mbps. 
    The sonic benefit I was hearing was indeed a result of crossing the A <-> B boundary, through the isolation moat. For the rest of my tests, I used the B side to connect to my music computer.
    Effect of grounding
    UpTone’s claim is that attaching a ground wire from the eR grounding post to an AC ground will remove “high source-impedance” leakage current from the SMPSes powering upstream devices connected to the network, by shunting these currents to the AC ground. This can raise SQ, although to what extent is highly system-dependent.
    In my network, I had already cleansed the path from my ISP ingress to my audio system of SMPSes. My upstream cable modem, router and switches were all running on LPSes. Perhaps for this reason, I heard no benefit from grounding the switch. I left the ground wire connected in any case.
    Effect of music location relative to switch 
    As I noted earlier, my local files reside on my NAS, so they traverse the switch during playback. However, the Stylus music player I use has an optimization where music can be cached on the boot drive prior to playback. Indeed, as a further optimization, the tracks in the queue can be buffered into memory prior to playback. A similar situation occurs in the case where a user’s music files reside on local storage downstream of the switch.
    In his white paper, Swenson notes: 
    “A very large buffer where the input completely shuts while all music is playing can eliminate the phase-noise overlay of upstream sources.” 
    Does this imply that the switch has less of an impact when the music files, either due to storage location, or due to the effect of pre-caching, are not flowing through the switch during playback? 
    To test this, I ran two player software configurations on my standalone music computer:
    Roon Server: Roon Core consumes track data from the storage device in a flow-controlled manner during playback. This represented the case where music data from my NAS was flowing through the switch during playback. Stylus: I configured Stylus with both cache and “buffer queue to RAM” optimizations. This represented the case where no music data was flowing through the switch during playback.  
    For each configuration, I compared the “no switch” with the “full monty” configuration. Result: both configurations benefited greatly from the full monty switch in the path. Even with no music data flowing in the buffered case, the switch still makes a difference. Moreover, the magnitude of the difference wasn’t significantly greater in the Roon Server case.
    This finding - of the switch making a positive impact on SQ even when no music data is flowing through it - also held when I compared the eR with its competitor switches. 
    Is the eR a perfect moat? 
    Any time a device claims to isolate with words like moat, it gets our hopes up that perhaps this device renders further optimizations upstream (or downstream) moot. To test this, I examined both sides of the eR.
    Effect of further downstream optimization
    If the eR upstream of the DAC-attached machine is a perfect moat, then is the reclocking JCAT Net Card Femto, with external SR-4 PSU, still necessary on my DAC-attached music computer, compared to a standard Ethernet port on the motherboard?
    I think you can guess the answer! Yes, it still makes a difference, even with the eR upstream of the machine. For all the good the eR does to SQ, it is not a perfect barrier. In my experience so far, no such device has provided perfect isolation. This does not detract from the value and benefit of the eR, but it just means it doesn’t remove the need for end-to-end optimization.
    Effect of further upstream optimization
    So if the eR is not a perfect moat, can SQ be further improved by adding an additional optimization upstream of the eR? To test this, I considered 2 scenarios, as shown below:
    In one case, I introduced my existing TLS OCXO switch upstream of the eR, connected to the eR via the usual copper Ethernet cable connection. In the second case, I introduced a Sonore opticalModule (oM) FMC (fiber media converter), connected to the eR via a fiber optic cable. The latter path has the advantage of galvanic isolation due to the use of fiber. Additionally, the oM is an audio grade FMC, using ultra low noise linear regulators, and a high-quality ultra low jitter FEMTO oscillator. The use of the oM also required the use of fiber transceivers and a fiber optic cable. For this test, I used the transceivers supplied by Sonore, which were TP-Link TL-SM311LM 850nm/550m transceivers.
    Both configurations further improved SQ over just the eR in isolation! I know this is the kind of improvement that, while appreciated, also induces a groan and a shake of the head. Where does this end?! Hold that thought - I’ll come back to that in a later section.
    Which configuration sounded better? While you might expect the air-gapped fiber path would hold the advantage, in fact these two configurations were very similar in terms of the additional SQ they added to the eR. The TLS OCXO switch configuration was stronger in enhancing the size and depth of the soundstage, while the oM configuration added more density, but was a little more closed in. 
    At this stage, I became aware of experiments being reported on several forums with different transceivers. Beware! This is another rabbit hole of endless experimentation, but I did dip my toe in the pool. After some experiments, I settled on a pair of the Startech SFP1000ZXST 1550nm/80km transceivers, with a 2m cable. Since these transceivers are designed for long  distances (note the 80km rating), I used 10dB attenuators, which also improved SQ. This combination was notably better sounding than the TP-Link transceivers. With this configuration, the oM leapfrogged the TLS OCXO switch. The oM added even more dimensionality, more meat on the bone, while also opening up the soundstage.
    I don’t want to suggest this kind of chaining is essential. The majority of the SQ gain comes from the eR upstream of the DAC-attached machine. The addition of the oM is like the icing on the cake. 
    Ethernet cables
    One axis I did not explore was to vary Ethernet cables. Since I’ve been experimenting with switches for some years now, I have tried many different cables in the past. Yes, cables do sound different in my system. Some time ago, I had picked the SOtM dCBL-Cat7 cables as the best fit for my system, for their rich and balanced character. For this review, I held these cables constant in all the comparisons.
    Comparisons with other audiophile switches
    I consider this section - the comparison with competitor products - to be the most important part of my reviews. How a component sounds in and of itself is interesting at best, but how it sounds relative to its competition is one of the most important pieces of information a potential buyer wants to have.
    I already had on hand my own units of the TLS OCXO switch and the SOtM sHN-10G. Full disclosure - at my request, @The Computer Audiophile requested review samples of the Aqvox SE and the Melco S100 switches. Neither were provided. Luckily, as is often the case, the community here came to my aid. A kind AS’er from Hong Kong loaned me his personal unit of the S100.
    I limited my comparisons to the SOtM and Melco switches. I didn’t bother with head-to-head comparisons with the TLS OCXO for a couple of reasons. First, there have been disturbing reports of quality issues and dubious business ethics by this company reported here on this forum. More tellingly, in my previous testing, the TLS OCXO switch was no sonic match for the sNH-10G.
    Without further ado, let’s see how the eR fared against these switches. 
    Comparison with the SOtM sNH-10G

    The SOtM sNH-10G (US MSRP $1700)  has been the primary switch in my system for some time now. It is a product SOtM designed from the ground up with audio quality in mind. In addition to Evox capacitors and linear regulators, the sNH-10G features their low phase noise, sCLK-EX clock board that can optionally be driven by an external 10MHz reference clock. This switch has 8 copper RJ-45 ports, and 2 SFP cages, all of which can operate at 1 Gbps.
     I compared the following configurations:
    For this comparison, I took a trip down memory lane and resurrected an album, Birds of Fire (Columbia - Legacy, 16/44,1) by one of my favorite bands, the Mahavishnu Orchestra. The track Open Country Joy is a joyous jam session between John McLaughlin, Jerry Goodman, Jan Hammer, Billy Cobham, and Rick Laird. Yeah - how could that not be amazing! This is by no means an audiophile recording, but it still revealed important differences. 
    Using the sNH-10G as my baseline, the eR sounded a bit cooler, which I felt was more tonally correct, while delivering  very similar soundstage size and resolution. At 1:11 in this track, when the violin, electric guitar, and drums kick in with a crashing crescendo, the SOtM came across a bit hot in the treble, while the eR sounded less fatiguing. The SOtM’s thinner sound contrasted with the eR’s more fuller signature.
    Across a wide range of tracks, I found these two switches had distinct signatures, but competed very closely with each other. In many cases, the sNH-10G had slightly better resolution, while the eR won on tonality and density.
    Overall, I preferred the SQ with the eR by a small margin. Once you factor in cost though, the eR won the price/performance battle handily. Given that the sNH-10G has been my reference switch for some time, this was an impressive showing by the eR.
    Comparison with the Melco/Dela S100

    The Melco S100 is a recently-released switch from Melco Syncrets Inc., and is sold under the brand names Melco in the UK and Europe (UK MSRP £1999) and Dela in Japan. It does not appear to be available in the US yet. The evaluation unit I was loaned was a Dela S100.
    Melco do not reveal much about what aspects of their design make this an audiophile switch. The 2-page datasheet claims that “Audiophile techniques are used in the power supply implementation with a bank of audio-grade capacitors…” but there are  no other details, including the quality of the clock. Effectively, this is just a black box with some claims of audiophile sound quality.
    The S100 has 2 banks of 4 RJ-45 copper ports. One bank operates at 1Gbps, and the other at 100Mbps. Additionally, there are 2 SFP cages for fiber transceivers. Melco claims that music streamers and players sound best when connected to the 100Mbps ports. In my listening tests, I did find this to be the case, although the SQ difference between 100Mbps and 1Gbps was not as large as the difference observed with the eR. Of course, in the eR’s case, data was also crossing the isolation moat. For this comparison, I used the 100Mbps on the S100, to compare the best possible sounding configurations of each switch.
    My preferences lean toward orchestral and symphonic music, so when I purchased this album, José, Albéniz & Manén: Guitar Works, Vojin Kocić (Naxos, 24/96)  as an impulse buy during a Christmas sale, it came as a bit of a surprise to find how much I liked it. I used the Cuba movement of Albéniz’s Suite española No. 1 to compare the two switch configurations.
    By this time, I had had the eR in my system for a couple of months, so I used it as my baseline configuration. I didn’t quite know what to expect of the Melco and had low expectations, so I was rather pleasantly surprised to find how good it sounded. Similar to the eR, it had a smooth, non-fatiguing tonal character. Soundstage size and resolution were also on par with the eR. The S100 surpassed the eR by a modest amount in its transient response of the guitar plucks, and the guitar sounds more solid and 3-dimensional. 
    Listening on other pieces, this advantage persisted, with the S100 portraying quicker transients with more density and saturation of the soundstage. This difference, while notable, was not huge. Still, in terms of absolute sonic performance, I would give the nod to the S100.
    How would I describe the choice between these 2 switches? If absolute performance is your goal, and cost is not a big consideration, then the S100 is an attractive option. However, the eR allows you to achieve similar SQ with a more incremental approach. Start with the $640 base switch, add an LPSU when funds permit, consider a reference clock down the road, perhaps even a clock upgrade after that. Finally, many users will value the information and transparency that UpTone provides, versus the black-box Melco approach. As with everything, it’s a choice, with no right or wrong answer.
    Chaining Experiments (down the rabbit hole)
    Finally, it was time to get into mad-scientist mode, and go chasing down the rabbit hole. Yes, I’m talking about chaining switches. I talked about this briefly in an earlier section, when I described the SQ increase by preceding the eR with the Sonore oM or the TLS OCXO switch. That experiment revealed that the eR was still amenable to upstream optimizations.
    Let me first preface this entire discussion to say - none of this is necessary, and I would hazard a guess that 90+% of eR users would never contemplate this! So read this section for vicarious entertainment, unless you are looking for the ultimate SQ and have the deep pockets to afford it.
    The premise here is simple.
    If one eR improves SQ as we found, would 2 in a chain improve further?  And by how much?  What about a chain of 3 eR switches?  
    Well, I can’t answer these questions, since Alex didn’t supply me with 3 eR’s - it was hard enough to pry one review sample out of his hands! However, I did have 2 other switches of similar quality on hand, so why not use those.
    My musical choice for this section was this new release of Beethoven Piano Concertos Nos. 2 & 5, Kristian Bezuidenhout, Pablo Heras-Casado, Freiburger Barockorchester (Harmonia Mundi, 24/96) came online on Qobuz as I was starting this experiment. Do we need yet another recording of the Emperor Concerto? Yes, if it’s this good! Bezuidenhout plays on a 1824 Conrad Graf fortepiano, which has some of the woody tone of early pianos, as well as the grander dynamics of the modern instrument.
    Effect of a 2nd switch
    I compared the single switch eR with a chain of SoTM > eR, as shown below.
    Sure enough, the 2-switch configuration sounded even better. What I heard was an amalgam of the best attributes of the sNH-10G and the eR. The excellent resolution and detail of the SOtM switch was evident, but teamed with the density and tonal richness of the eR. 
    Just for grins, I flipped the order of the switches, and was surprised to find it sounded … different. Mostly, there was a more forward, thinner sound I didn’t quite like as much. I found I much preferred the SoTM > eR chain. It appeared the sonic signature of the last switch in the chain was the dominant one, which is perhaps not surprising.
    Copper vs. Fiber
    Since I had had a good experience with the  Startech SFP1000ZXST transceivers, with 10dB attenuators, I was curious to see how this fiber optic path would fare in the 2 switch configuration. The answer is - very well! Comparing the copper path to the fiber path, I found I greatly preferred the fiber path, and indeed this difference was even greater than what I had heard comparing the oM and the TLS OCXO switch. Note that in this deployment, everything else was constant, including PSUs and clock, so the only change was between copper or fiber between the switches. The fiber path had cleaner transients, and sounded more coherent. And with the Startech transceivers, there was more density and saturation to the soundstage. I could have gone down a secondary rabbithole of trying more transceivers, but decided to leave that to others! As I finish this review, there appears to be another promising prospect from Planet Technology being reported on the forums, which I will try in due course.
    So did the second switch deliver the same value for money? Well, no. The bulk of the improvement comes from the first switch. The second switch is definitely a step up, but the incremental gain is a fraction of the first. To those looking for absolute performance, this is very worthwhile, while those looking for value will likely not consider this a good return on investment.
    Effect of a 3rd switch
    Why not go for broke and chain all 3 switches? Why not indeed! Fortunately, I had the spare PSU rails to try this.
    What can I say? Incredibly, the 3rd switch does in fact add a small dollop of additional SQ. Do I recommend anyone do this? Not really, although some fanatics might. For me, it really comes down to value for money. With a 2-switch chain in place, wouldn’t the cost of the 3rd switch and a PSU (rail) be better invested elsewhere in the system for a bigger sonic impact? I’d certainly want to explore that.
    If you’re exhausted at this point, consider my predicament! Luckily, I enjoy experimentation, so this was fun for me. Still, I had to be disciplined and follow a written plan to make sure I covered as much as I did. And with all that, there are so many configurations I couldn’t test.
    In this section, I want to put all the findings in this review into some context, as key take-aways. One of the dangers of describing SQ improvements in relative terms is that it is easy to lose sight of the actual magnitude of the improvements. So here are some reflections, based on my own subjective experiences:
    The SQ gains from Ethernet improvements in aggregate are significant, and comparable to USB improvements (regenerators, cables, etc). In my system, the total magnitude of USB optimizations has tended to yield greater aggregate SQ, but I consider both areas of network and USB to be fertile ground. The SQ improvement from the combination of switch, PSU, and clock is comparable to making a component upgrade (for example, a DAC or amp) of similar price. I know this a provocative statement, and may not always hold, but it highlights my own experience that upstream improvements deserve appropriate investment, and deliver similar value SQ improvements from chaining switches are additive, but asymptotic. By this I mean additional switch(es) provide diminishing returns, so consider value for money carefully before taking this approach. SQ improvements in the chain, especially in the network path, are very system dependent. Take my findings as data points, but always verify for yourself if the improvements manifest in your system, and if what you hear is worth the cost. This is where the satisfaction guarantee of products, like the 30-day money-back policy for the eR, is incredibly important.   
    The UpTone EtherREGEN is one of those rare products that delivers high-end audio performance at an affordable price. Not only does it deliver “surprisingly audible sonic improvements” as claimed, it holds its own against the best-sounding competing products out there, that cost 3x its price or more.
    Furthermore, unlike any of its competitors, UpTone have attempted to demystify the technical basis for the product, and are to be commended for that. Whether or not it convinces the skeptics, I for one applaud their transparency in the matter.
    For a modest investment, users can start with the sonic benefits out of the box, and extend these benefits further over time with upgrades to the PSU and clock. With this stepwise approach, users can achieve similar absolute performance as the best of the EtherREGEN’s competition.
     I don’t use the word “bargain” lightly, but in this case it’s true. The EtherREGEN is one of high-end audio’s bargains. If your audio system uses Ethernet for streaming audio, you owe it to yourself to try the EtherREGEN.
    Product Information:
    Product:  UpTone Audio EtherREGEN Price: US MSRP $640 Documentation:  EtherREGEN User Guide  
    Associated Equipment
     Primary System
    Music Computer:          Custom computer: H370M-ITX/ac, i7-8700T, 8GB Apacer RAM, HDPlex H3 case,  32GB M10 Optane SSD for                                              OS, JCAT Net Card Femto, running Euphony OS with Stylus or Roon+StylusEP music software Music Storage:               Synology NAS DS916+ 4-bay, attached to router via Ethernet Headphone Amplifier:    Cavalli Liquid Gold Headphones:                 Sennheiser HD800 (SD Mod), Meze Empyrean, Abyss AB-1266 CC USB Regenerator:         SOtM tX-USBultra SE Reference Clock:           Mutec Ref 10 10MHz clock driving the tX-USBultra and switch Power supplies:             Paul Hynes SR-7 DR (dual regulation)  for switch & tX-USBultra, Paul Hynes SR-4 for JCAT Net Card                                                             Femto, HDPlex 400W ATX LPS for music computer motherboard Power Details:               Dedicated 30A 6 AWG AC circuit, PS Audio P12 PerfectWave Regenerator (under review) Power Cables:               PS Audio AC-12 (wall to P12), Cardas Clear Beyond (Cavalli Amp), Cardas Clear for all other components USB cables:                   Intona Ultimate 0.5m, Intona Reference 0.5m Clock cables:                 Habst 5N Cryo Pure Silver 50Ω and SOtM dCBL-BNC 75Ω Ethernet cables:            SOtM dCBL-Cat7 DC cables:                     Ghent Audio custom OCC JSSG360 ATX and EPS cables, Paul Hynes fine silver (SR-4, SR-7) Interconnects:               Cardas Clear XLR balanced Headphone cables:       Transparent Ultra cable system, Cardas Clear balanced and SE cables Accessories:                  Synergistic Research Tranquility Base XL UEF with Galileo MPC  
    Many thanks to the following companies for supplying cables and accessories to aid in this evaluation: 
    Cardas Audio, for a full loom of Cardas Clear cables. Transparent Audio, for the Transparent Ultra headphone cable with a full complement of headphones leads and source terminators. Intona EU, for the Reference and Ultimate USB cables. Sonore Audio, for the opticalModule, TP-Link fiber transceivers, and fiber optic cable.  
    About the Author
    Rajiv Arora - a.k.a. @austinpop - is both a computer geek and a lifelong audiophile. He doesn’t work much, but when he does, it’s as a consultant in the computer industry. Having retired from a corporate career as a researcher, technologist and executive, he now combines his passion for music and audio gear with his computer skills and his love of writing to author reviews and articles about high-end audio.
    He  has "a special set of skills" that help him bring technical perspective to the audio hobby. No, they do not involve kicking criminal ass in exotic foreign locales! Starting with his Ph.D. research on computer networks, and extending over his professional career, his area of expertise is the performance and scalability of distributed computing systems. Tuning and optimization are in his blood. He is guided by the scientific method and robust experimental design. That said, he trusts his ears, and how a system or component sounds is always the final determinant in his findings. He does not need every audio effect to be measurable, as long as it is consistently audible.
    Finally, he believes in integrity, honesty, civility and community, and this is what he strives to bring to every interaction, both as an author and as a forum contributor.
  7. Upvote
    Gavin1977 reacted to bobfa for an article, Allo USBridge Sig Review   
    This is a slightly different review for me.  It is hardware review that focuses on a lot of software not supplied by the hardware vendor.  It is also about integrating both hardware and disparate software systems. Finally, the end results totally surprised and delighted me and everyone else who has participated.
    The Allo USBridge Sig arrived with the Volumio software installed. Since I reviewed the Volumio Primo over the summer, I thought that starting using the Volumio on the Allo was a great idea.  
    As a refresher, Volumio software is a complete music playback system for local files, streaming services, and Internet Radio.  Volumio is a complete Linux OS with a competent and flexible music player that is lightweight and designed to run on small computers. MyVolumio is an add on SAAS component to bring more services to play.
    The Hardware 

    By using the Raspberry Pi 3+ compute module instead of the standard Pi 3+, Allo gains the flexibility to provide dedicated external interfaces.  The USBridge Sig board is engineered to isolate the ethernet noise from the compute module and to isolate the clean USB port for your DAC.  By providing the standard 40 pin interface connector, they give access to HAAT systems such as the DIGIONE Signature SPDIF board installed in the case I have.
    There are two separate power supply inputs on the case, one for the mainboard with the Pi computer and one for the DIGIONE board set. The Shanti power supply manages this with its two outputs.  The Shanti is a linear power supply with super-capacitor outputs.  It ships with multiple adaptors for different input connections, providing two fixed outputs 5V 3A and 5V 1A as a match to the Pi boards and HAATs. 

    Allo has “earth” or ground binding posts on both the Shanti and its case for the USBridge Sig.  Allo is very insistent that you run a separate grounding connection between the devices and include your DAC if there is a way to do that.

    That wraps up the hardware and a once over lightly for the Volumio Software.  Now to the testing and how does it sound?
    First, let's set the “sound-stage!”  
    The Software
    I am working through four Operating Systems that provide different services on the Allo USBridge Sig in this review. 

    Ropieee is a Roon endpoint application, and it has an XL version that does more. DietPi is a general-purpose Linux implementation for the Pi. Volumio is a music playback system that is a stand-alone and multi-room music playback system that also an SAAS component.  MoOde audio player is a stand-alone “Audiophile-quality” music player.  
    I flashed microSD cards for this testing.  They are The V30 speed cards, and they help performance on Volumio and MoOde Music Players. I want to try the faster UHS II V60 or V90  cards to see if they improves performance.
    Here are a couple of notes of caution going down the software path that this hardware leads us.
    Qobuz in the open-source world   Qobuz was suffering theft of services against their service.  They have made several changes that, in effect, shut out some Open Source systems access.  Today for my testing, I cannot merely use DietPi to play Qobuz streams.   Problems in the Linux 4.19xx kernel   As of this writing, the current version of the Linux kernel used by some of the player software has a defect that causes clicks/pops to some DSD DACs.  (Including mine)  
    This testing involved lots of learning and unlearning.  There is fussing / fiddling around with software and settings and a whole lot more.  I have shut down, rebooted, yanked the power, swapped USB cables, and typed on the Linux command line for a lot more hours than ever before!  As an example: after Volumio I moved over  to MoOde to get a feel of how it worked. I did a terrible job of reading, let alone understanding MoOde.  The underlying music player software is MPD, and you have to configure MPD with your USB DAC attached.  Read the Manual! Get on their forum for help.
    I did some of my initial listenings on my Schiit LYR3 with multi-bit DAC and with my Chord Mojo. The results were rather promising, and it helped with the break-in.  Then I moved into my main system and spent a few days listening, bouncing between my Server and the Allo.  The Allo started on a good foot and over time, it really hit its stride.  After about three weeks of on-time things were very stable!
    The Hook-up
    I have the USBridge Sig connected directly to my Ethernet network, and my Xeon based server/streamer connects via an opticalModule Fiber Media Converter to the same network.  I swap the Lush2 USB cable from the Xeon box (+tXUSBultra) to the USBridge Sig. 
    My Xeon box runs Euphony OS so it can swap around between the Roon components and Stylus player.  I have primarily been running it with Roon + StylusEP.
    I have an i7 NUC in my office that I also have Euphony OS on.  It runs as a second Roon server.  Again it as the same flexibility.  It is connected to the Ethernet network directly.
    My music library is on a QNAP NAS located in the basement.  There is no extraordinary power or network, just Ethernet, to the main Ubiquiti Switch.
    My system setup before the testing is shown in my profile here on AS:
    @bobfa Audio System
    Beginning to Listen: FINALLY! 

    First we have to have music!
    I want to thank @The Computer Audiophile and @austinpop and Kii Audio for their Qobuz Playlists. They are very helpful in finding a variety of music and not get stuck on “that one track.”   I have also added a playlist of some of the tracks I use.  I have more but this gives you a flavor.
     Audiophile Style 50 austinpop's dCS Bartók Review Playlist (Qobuz - US) Kii THREE BXT bobfa's USBridge Sig (Review play list)  
    There are dozens of permutations, hundreds of settings and options that I could have tried.  I have kept this “simple” I am using three configurations. On Device Music Player, Squeezelite, and UPnP.  Where Possible!
    I started my actual listening tests using Ropieee as the Roon Bridge. I was disappointed in the sound quality.  Many of us have found that Room Bridge has some limitations. We have moved to Squeezelite. My time with Ropieee ended rather quickly.
    I setup DietPi next, and to be honest, I did not bother listening to it much at all.  I did not want to learn how it worked to run different software packages, too much GEEK!.  Maybe it was just a bad day. I want to listen to music, not manage another computer.  If there is time later, I will setup DietPi and compare it to the others.  Yes, I have to read the manual!  I am sure I am not giving DietPi a fair shake yet.  
    That left me with two options to work with: Volumio and MoOde!
    As noted above, I started with Volumio and MoOde as a stand-alone streaming solution against Roon+StylusEP on my Server.  I could not conduct some of my tests fairly as Volumio can do Qobuz via SAAS, and MoOde only plays local files without a different control point application. 
    Volumio works fine on the USBridge Sig, I had some problems with the iOS App finding the Allo on the network.   In the end, Volumio did not sound as good as MoOde.  It lacked clarity and depth in comparison.  I have now narrowed myself down to one OS, WHEW!  
    The MoOde player's user interface is pretty simple and clean.  Using the UI on small screens is hard.  On a large iPad or a laptop it is fine.  My system also has a large display hooked up to the Allo.  I use a cordless mouse to navigate.  MoOde has surprised everyone who has listened to it on my system.  It is great!  In any mode we tried.
    I am still trying to find a good UPnP control point for iOS devices.  I guess good is relative.  I finally got MConnect HD working on the iPad after finding a bug that took me two days to work out.  USE the GEAR icon to find your renderer. I also used BubbleUPNP on my Android Phone.  Of course, that is not all you have to do.  You need your local music on a device that is UPnP.  Fortunately, all I had to do is to configure Plex on my NAS to include my music folder.  
    During listening, I did not bother to search in Mconnect ; I just ran down the file/folder structure.  For some reason, there is no artwork displayed. I was mostly getting the PLEX logo on my local library.
    This testing showed much more of the promise coming from the Allo, but, I had to pause this project for about 10 days. 
    At this point, I was dizzy trying to keep notes flipping back and forth, WHEW.  I had my friend Rich come over for coffee and music. Comparing the Allo and my Xeon server has been a self-defeating process.  I have been so happy at my progress in building something that sounds so great.  Only to be squarely kicked in the rear by the Allo USBridge Sig!  
    In summary, I think that my friend Rich said it best; he would be happy with either device!  After another few days of listening, I have to agree.  BUT WAIT THERE IS MORE!
    I switched MoOde over to Squeezelite and started using it as a Roon endpoint.  So now, the software paths are similar. We are “closer” using Squeezelite on the Allo and StylusEP on the Xeon.  The made the A/B a bit simpler as long as they did not crash the USB bus!
    We have a photo finish. The imaging is almost identical. I had some help with blind A/B testing, and it is to the point I have a tough time telling the difference.  There seems to be a bit more detail in the USBridge Sig and a little more harmonic fullness in the Xeon box.   
    This past weekend my friend Eli came over and listened.  He made many of the same conclusions that others have made.  The USBridge Sig is a great piece of hardware with the right software to make it shine.  (There will be more notes in my upcoming update on the DIGIONE Signature boards)
     The last lap
     Can I make the USBridge Sound Better?
     (Note that during this testing I was using MoODe with Squeezelite)
     While I was at this, I created a side project to try to “improve the sound quality” from the Allo!  
     I did an A/B with and without the txUSBultra connected between the Allo and the Kii Control.
    While this did make a difference, it was not enough to even consider back ending a $1500 device on the Allo.  The USB side of the USBridge Sig does its job, Thank You Very Much!
    The next A/B trial was to move my Sonore opticalModule to the Ethernet input on the USBridge.  I did not spend much time listening as I had to reboot on every change for some reason. I did not hear any difference with the FMC inline.
    Note that the opticalModule makes a very noticeable difference when connected to the standard Ethernet port on my Xeon server.  Again the folks at Allo seem to have done a great job on the input side.
    In Summary: The Hook-up
    Note that I fronted the Shanti power supply with a Transparent Generation 5 High-Performance Power cord. Yes, the cord costs more than the Shanti!  
    The USB cable I am using on the output of the USBridge Sig is the Phasure Lush’2 cable as the last link to the Kii Control.  But again, this cable is around $250, which is more than the USBridge Sig board costs!
    I feel that it is a very fair testing method, keeping everything the “same” around the unit under test. 
    In summary, the Allo USBridge Sig is an excellent value for the money, and it plays well above its price class.  Buy it in the bundle with the Shanti power supply and get the metal case; it is worth the price! 
    The hardest part of this review was starting to learn how all the different software packages work and finding software to do thinks like UPnP.    It is my understanding that Allo is working on improving the software situation!  
    Software and hardware stability in these rather complex systems can be a problem. Once running, the systems were stable during most of the testing. 
    To be completely open: more than once, I confused the USB interface on the Kii Control by swapping between devices, and that caused me to have to power it down.  I am having software issues with Roon on Euphony OS (RAM Loaded), as the system would stop talking to the DAC over USB that I am still debugging.  The problem seems to be around the audio endpoint in Roon.  I am seeing this on both of my Roon boxes and with other DACs.
    Going forward, I am set up to test the DIGIONE Signature board set on the USBridge Sig card. Expect additional reporting on that soon.
    In closing, I almost hate to admit that the USBridge Sig with the Shanti power supply sounds better than my custom-built Xeon.
    Just One More Thing!

    As I was finishing up my review I had to go back over my listening and my configurations, ONE MORE TIME.  I started back using the Allo as the render in with Roon on the NUC server and Squeezelite on the Allo.  
    Then I went back to native MoOde and UPnP for Tidal and Qobuz.  The soundstage opened up, there is more detail.  Vocalists are more defined.  Listening at lower volume levels is even more satisfying.  
    Maybe there is something to what I have heard about MPD sounding the best? The MPD/UPnP path eliminates a lot of software, network traffic. 
    I am now using the USBridge Sig as the main / only device in the music system and I am  storing the local music on my NAS with an SMB share with the moOde Player.  Adding in streaming from Qobuz and Tidal using Mconnect HD rounds out the mix.  So one app on the iPad for streaming and Safari Web  browser for local music playback.   This is not Roon but it works and sounds great!  I will run with this for a while and see how we all feel operating the system.  I know that I will be happy to just listen for a while and not be testing.  
    Bob Fairbairn
    OK, OK; I still have to do the DIGIONE Signature !  I promise.
    Product Information
    USBridge Sig  Board is $239 (link) DIGIONE Signature boards $239 (link) Shanti Power Supply $159 (link) Case for Board only is $20 (link) Case for Board with space for DIGIONE $23  
    **Look into Allo combination pricing!
    Other equipment in the mix
    Kii Three + BXT + Kii Control
    Xeon server with HDPlex400
    Custom NUC with HDPlex200
    Modified SOtm txUSBultra
    Sonore opticalModule
    Lush2 USB
    Ghent JSSG360 USB
    Transparent HP USB
    Transparent HP Ethernet
    Ghent JSSG360 Ethernet
    UpTone Audio LPS-1.2 running the txUSBultra 
    Transparent Audio HP power cables and power bank 6
    Ubiquity UniFi Network 
    Primary Software used
    Bubble UPnP on Android
    MconnectHD on iPad for UPnP
    MConnect on the iPhone for UPnP
    MoOde OS
    Volumio OS
    Euphony OS
    Squeezelite Roon Endpoint
    StylusEP Roon Endpoint 
    Plex server on QNAP NAS
    The purpose of life is not to be happy.
    It is to be useful, to be honorable,
    to be compassionate,
    to have it make some difference
    that you have lived and lived well.
    Ralph Waldo Emerson
    “Enjoy the music and the fun.”
  8. Upvote
    Gavin1977 reacted to Sonis for an article, Chord Electronics Qutest DAC Review   
    Chord Electronics of England is a high-end audio manufacture known for its somewhat quirky product design and high performance. Over the last couple of years, Chord has made quite a splash in high-end circles with its Digital-to-Analog-Converters (DAC for short). Starting with the iconic (and very expensive) “Dave” model DAC/Preamp in 2015, Chord released a number of DACs using the unique FPGA (Field Programmable Gate Array) based multi-bit DAC designs of Rob Watts. Watts' designs use the FPGA to incorporate a “practical” approximation of the theoretical “ideal infinite interpolation filter” in a DAC as described by Nyquist and others. Most DACs have filters with about a hundred coefficients or “taps” which give most digital filters decent sound. Watts feels that most DACs have far too few taps to give good transient performance. According to Watts, transient performance in a digital reconstruction of an audio signal is probably the most important part of that reconstruction because human hearing depends on our perception of transient information to accurately hear such musical cues as pitch, timber, and image specificity as well as the overall accuracy of the soundstage. The Dave DAC/Preamp has 164,000 taps which is more than ten times the number of taps in any previous Chord DAC.
    After the Dave Chord produced the Hugo and the Hugo 2, which are DAC/headphone amplifier combos using Rob Watts’ unique multi-bit decoding but with fewer taps. There is also the Hugo TT which is supposedly the tabletop version of the Hugo 2, without the battery powered headphone amp but with twice the number of taps as the Hugo 2. The Hugo 2 has 49,152 taps and the Hugo TT has 93,304!
    More recently, Chord has introduced the “Qutest” which is supposed to be the non-portable version of the Hugo 2, but sans that unit’s headphone amplifier and Bluetooth support. The Qutest also replaces Chord's earlier effort at a less expensive multi-bit, multi-tap converter, the “2Qute” at US$1495. While the Hugo 2 sells in the US for $2,695 the Qutest is much more affordable at US$1,895. 

    First Look
    While the Hugo 2 is an aluminum rectangle of 10cm (3.94”) wide, by 13.1cm (5.16”) deep and 2.3cm (0.9”) high and weighs 450g (16 oz), the Qutest is 16cm (6.3”) wide by 8.8cm (3.46) deep by 4.5cm (1.77) high and weighs 770g (27 oz. Yes the smaller Qutest is heavier than the Hugo 2). Both units are available in either silver aluminum finish or black aluminum finish. 
    Anyone who has ever seen a Chord component (or even a picture of one) knows that their design is somewhat quirky to say the least and definitely outside of what would be considered the normal audiophile equipment look. While this is certainly true, one look at either the Hugo II or the Questest will certainly attest to the build quality of these components. The Qutest, which is our interest today is shaped like a slightly smaller version of a standard paving brick. The corners are all hard, right angles and the case seems to be machined out of a solid billet of aluminum. On the top of the unit there is a central, oval shaped window of glass that seems to be a magnifying glass lens of around 2 inches in diameter. When powered-up the interior of the box, through the window, lights up with the sampling rate indicator displaying the sampling rate through the light changing color from red, through blue and purple to indicating DSD.  One can see the printed circuit board with the word “Chord” stenciled on the board in white, followed by the words “Designed by Robb Watts”. In the upper right-hand corner of the outside case is a chromed plaque riveted to a recess in the casework with the Chord Logo embossed in black.
    The front lip of the case has two scalloped-out recesses each holding what look like clear marbles set into each. The front of the case identifies these as push-button controls, labeled, left to right as “Filter” and “Input” respectively. 
    Turning to the back of the unit we see a number of I/O connections starting with the type “B” USB jack (up to 32-bit/768KHz PCM and 512 DSD) located on the extreme left. Next to the USB input are a pair of gold plated BNC receptacles labeled BNC IN, 1 and 2 (24-bit/384KHz dual-data mode capable to 768 KHz). These are primarily intended to connect the Chord's optional and not cheap digital Hugo M up-scaler (although one suspects that they can be used as coaxial SPDIF inputs as well) and as an interface to the M scaler is beyond the scope of this review (for more information about the Hugo M scaler, see @austinpop's review of the HugoTT 2/M scaler posted here on Februrary 21, 2019 entitled: “My Quest for a New DAC, Part 5”). Dead center to the back panel is a single Toslink optical digital input (SPDIF 24-bit/192KHz and DSD 64) and to the right of that, we find the obligatory analogue outputs consisting of two gold-plated RCA jacks marked Right and Left. To finish off the back panel is the 5volt USB power input jack of the Micro-B type. That constitutes the entire I/O and control facilities of the unit. 

    Using The Qutest
    After connecting the digital input to the Qutest via either USB, coaxial or optical (Toslink) SPDIF, one selects that input by stepping through the available selections by color: USB – Clear, Coax 1 – Yellow, Coax2 – Red, Optical (Toslink) – Green. All functions and sample rates are indicated on the Qutest by colored LEDs. Next, one can step through the available filters: Incisive neutral – clear, Incisive neutral with High-Frequency Roll-off – Green, Warm – Orange, Warm with High-Frequency Roll-off – Red. 

    One can set the variable line level output by holding down both the Filter and the Input button  for the first 16 seconds on power-up. After 16 seconds release both bottons and press them again repeatedly to set one of the three desired fixed audio output levels. 1 volt RMS is Red, 2 volt RMS is Green, and 3 volt RMS is Blue. Most audiophile equipment is designed around a line-level input of about 2 volts. My suggestion is to start there, and adjust up or down as needed to best equal the input level of one’s other analog inputs to one’s amplifier. This will avoid drastic changes in volume when switching from input to input on one’s stereo amplifier.
    That’s pretty much it for setup and operation. The Qutest will automatically switch between sample rates and PCM/DSD modes based on the inputs. Now all that is needed is to sit back and listen.
    Listening to the Qutest
    Back in February of this year, an audiophile buddy of mine bought a Chord Hugo 2 DAC/Headphone amplifier. He brought it by and left it with me for about a week. I was flabbergasted, gobsmacked, and delighted by what I heard. I have a live recording that I made many years ago of a very good symphony orchestra playing Ravel’s complete “Daphne et Chloe” ballet complete with large chorus. I always thought that the recording sounded very good, very natural. But through the Hugo 2 and the HiFiMan Jade 2 electrostatic headphones, I heard things in that recording (16-bit, 48 KHz) that I wasn’t even aware were present in the recording. Now, I had listened to this recording through the Jade 2 ‘phones before, and while they were undeniably a great pair of transducers, they didn’t really unveil anything in that recording with which I was not familiar. The Hugo 2 changed all that. Of course, I couldn’t keep the Hugo, it didn’t belong to me so it went back to its owner at the end of the week. I'd read that the  Qutest was the same DAC sans the headphone amplifier and the battery power, so I arranged to borrow one from Chord for a review. 
    Fast forward to July. I received the Chord Qutest from Bluebird Audio and started to “burn it in”. After letting it “cook” for about a week, I cued up the “Daphne” and sat down to enjoy, once more, the magic that I had experienced in February with the Hugo 2.  No Joy! While the Qutest is indeed a very good DAC for its approximately $1900, the magic of the Hugo 2 was missing. Now, my normal “reference” DAC is a Schiit Yggdrasil v.2 and it sounds generally better than most DACs in it’s price range, but the Hugo 2 is more expensive and with its almost 50,000 filter coefficients (taps), it should have vastly better performance than the Yggy. That being the case, I wasn’t too surprised that my buddy’s Hugo 2 bested my Yggy. Since the Hugo 2 and the Qutest shared the same DAC circuitry, I expected nothing less than the same jaw dropping sound that the Hugo 2 produced. 
    To say I was disappointed was an understatement. I again prevailed upon my friend to borrow his Hugo 2 and compared the two directly. With the Hugo, the magic was back, when I switched to the Qutest – not so much. The Qutest reminded me so much of the Yggdrasil, that in a double-blind-test, I’d be hard put to tell the difference. Now, That’s not bad at all. A ladder DAC (R2R) that sounds as good as a multi-bit Yggdrasil and yet costs about $500 less is a bargain in anyone’s language, but I was determined to find out why two different iterations of the same circuit should sound so different. 
    I started out looking at the differences. The Hugo 2 is a battery-powered device with a built-in headphone amplifier. The Qutest, on the other hand, is powered directly from it’s own 5 Volt USB wall-wart and has no headphone amp. Now I wasn’t using the headphone amp (although, through the headphone amp powering a pair of HiFiMan Edition X v.2 phones, the “magic” of the Hugo 2 was still much in evidence. I decided that the headphone amp was not the problem, and indeed was irrelevant. That left the power supply as a possibility. Even though the Hugo 2 was powered by a battery, that battery was charged with with, again, a 2 amp USB charger. 
    I own one of those emergency car battery eliminators that can be used to start a car in case of a battery failure. You know the type,  About the size of a construction brick, consists of a large enough Lithium Ion battery to start a car or pickup truck several times using the included jumper cable set. One charges the battery with the AC in one’s home or garage, and carries it in the car for emergencies. Mine has an added feature of a 5 Volt USB port, meant to recharge cell phones when one is away from home or other sources of USB recharging power. Brainstorm! Why not replace the Qutest’s USB wall-wart power supply with the emergency battery eliminator! 
    I connected the Qutest to said auxiliary battery supply figuring that, now the Qutest is being powered exactly like the Hugo 2. So if it’s in some way the pure DC from a battery that’s accounting for the difference in sound performance I was experiencing, this should level the playing field. Again, I noticed no difference between the Qutest on battery power and the Qutest on mains-derived 5 V USB power. There has to be some other reason why these two supposedly identical D-to-A circuits sounded so different. All other things being equal the difference would almost have to be in each unit’s analog output stage. I have no way of knowing how the two line-level output stages differ, but clearly they do.  The web-site spec sheets are no help as the Qutest shows the specs for the line-level output and the Hugo 2 spec sheet shows the specs for the headphone driver amp – which when listening through the line-level outputs has no relevance to to the Qutest output. 
    The Chord Qutest is a very high-quality, well made Digital to Analog Converter. It is small, inconspicuous and presents performance on par with much more expensive R2R (ladder) DACs. From what I can deduce, the audible performance is almost identical to that of a Yggdrasil with the improved filter and at US$1895 it’s $500 cheaper than the US$2399 Schiit Yggdrasil. 
    But If you want the performance of a Hugo 2 then you will have to buy a Hugo 2 (or, better yet, a Hugo 2 TT). In spite of the similarities with regard to the actual Digital-to-Analog Conversion, while the two units are certainly similar, the Hugo 2 gleans more detail from high-quality material than does the Qutest. Having said that, I still believe that if you are in the market for a quality DAC under Two thousand dollars, you’d be hard pressed to find a better sounding one, and believe me, I’ve auditioned most of them.
    Product Information:
    Product:  Chord Electronics Qutest DAC ($1895) Documentation:  Chord Qutest DAC Manual (10.7 MB PDF)  
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