Jump to content
  • The Computer Audiophile
    The Computer Audiophile

    Review | Boulder 866 Integrated Amp

     

    RAAL SR1a 01.jpgAs many Audiophile Style readers know, I fell in love with the RAAL-requisite SR1a headphones this year (link). They are the first true ribbon headphones and have very unique power requirements. Other than using one of only two direct drive amplifiers made specifically for these headphones, from Schiit and RAAL-requisite, the SR1a must be driven by a traditional power amplifier. In other words, these headphones connect to a power amplifier's speaker output terminals, with an interface box between the speaker cables and the headphone cable. It's a configuration that I absolutely love because it opens up these headphones to the world of high end amplifiers. Why wouldn't I want to power the most sensational audio product I've ever heard with an amplifier from one of the best companies in high end audio?


    With this in mind, I set out to acquire review samples from Parasound, Constellation Audio, and Boulder Amplifiers. Each company offers something unique that really scratched my itch to take the SR1a to the next level. My evaluations of the Parasound HINT 6 and Constellation Audio Inspiration Integrated are ongoing, but I'm finished putting the Boulder 866 Integrated through every test imaginable and listening through it for countless hours. OK, not quite finished listening because I have my headphones on as I type this review. Someone pinch me, the world is close to coming out of a global health pandemic and I'm bathing in sound quality, build quality, and enjoyable musical experiences on an incredibly high level. 

     


    A Little Background

     

    A few quick notes on my requirements and why I selected the Boulder 866 Integrated for this review. The SR1a headphones and interface box present a 5.6 ohm load to the connected amplifier. This configuration requires an amp with at least 100 watts and in my experience the amp must be fantastic and without flaws, to make these headphone shine. Think about it this way, have you ever placed your ear right next to a tweeter and listened to the grunge and noise that some amplifiers emit? While that's an experiment done only for kick and giggles, listening to the SR1a headphones is a serious endeavor that places even more extreme requirements on the audio system. Wearing these headphones is like placing one's head less than one inch away from two full range, incredibly transparent speakers, and listening for hours on end. If there's a sonic issue with an amplifier, I will find it using the RAAL-requisite SR1a. Conversely, if an amp is among the best, these headphones will reproduce music on a level that's second to none. 

     

    RAAL SR1a 02.jpgI must also clearly state that using the SR1a headphones with an amplifier like the Boulder 866 Integrated is completely different from connecting other headphones to the quarter inch jack of an integrated amp and letting 99% of the power remain unused. The SR1a are demanding and will push amplifiers as far or farther than a pair of loudspeakers. I know it sounds strange for those who haven't experienced the SR1a, but it's really a special headphone on many levels. 


    I specifically reached out to Boulder Amplifiers for its 866 Integrated because the unit checked all the boxes I needed for my integrated amp research. I needed a one box solution that isn't too large, offers plenty of power, is designed by extremely competent engineers, supported by a great company, has digital inputs, and looks great sitting next to me on my desk, where I wear my headphones most frequently. I purposely selected other amps for my research that offer different features, that I'll go further into during those reviews. 

     


    Boulder 866 Integrated

     

    The Boulder 866 Integrated amp is offered in two configurations, all analog ($12,250) or analog and digital ($14,450). I selected the analog and digital version because I wanted this to be a one box, elegant solution for my headphone system. Visibly, both versions are identical except for the digital inputs on the rear of my review unit. The metal work on the 866 chassis is classic Boulder. It's unique, built like a brick outhouse, and oozes class and quality. Even the buttons on the front panel have a very solid feel to them when pressed. The weight of the 54 lbs chassis also means the unit doesn't budge an inch when pressing the buttons, unlike some components that slide back on a rack or desk when the front panel is touched. 

     

    RAAL SR1a Boulder 866 HERO.jpgThe front panel also features a full color touch screen that displays album art large enough to be seen from across a room. This touch screen also enables one to configure the unit in a limited way if needed. I recommend using Boulder's iOS app for configuration and adjusting this front panel display because it provides options unavailable directly on the display. For example, using the iOS app I added custom icons for the analog inputs, that displayed logos for Berkeley Audio Design, dCS, and EMM Labs. All companies whose DACs I connected to these inputs during this review. One thing that shouldn't be overlooked is the simplicity of the touch screen and iOS app interface. This is an incredibly easy device to use and setup. 

     

    Prior to writing this review I interviewed the Boulder team about the 866 Integrated and gleaned a bunch of information that I know is of interest to the Audiophile Style Community. First and foremost is the Raspberry Pi 3 B+, single board computer that handles some of the 866's digital duties. Previous Boulder components have used the Beaglebone platform, but the 866 has additional requirements that made the Beaglebone too underpowered for this application. Like all Boulder digital components, in the 866 the company opts to digitally oversample the audio prior to delivery to the DAC chips. All audio that enters the 866 via Ethernet or via USB hard drive (PCM and DSD) is oversampled by the Raspberry Pi 3 B+ to 24 bit / 352.8 kHz using Boulder's proprietary algorithms. Thus, the need for a more powerful single board computer than the Beaglebone. Audio that enters the 866 via AES or Toslink is oversampled via FPGA rather than routing this signal back through the Raspberry Pi. 


    The Raspberry Pi based Ethernet input is Roon Ready (certified) and can accept DLNA streams from any DLNA compliant server. Attaching a hard drive to a USB port of the built-in Raspberry Pi enables one to browse the music stored on the drive, via the iOS app, but the experience leaves a lot to be desired. I use the 866 Integrated as a Roon Ready endpoint for 99% of this review period. 

     

    The Ethernet interface of the 866, handled by the Raspberry Pi, had no problems accepting audio up through 24 bit / 352.8 kHz. I experience zero pauses or stuttering during playback. I also tested the built-in wireless capability and had surprisingly great results. The 866 has no visible WiFi antenna, leading me to believe it would be somewhat limited to lower sample rates. I successfully played DSD64 and up through 24 / 352.8 without a single hiccup via wireless. Technically the unit can accept up through 384 kHz, but I couldn't find any of my 384 content to test. Also of note, the unit's maximum DSD rate is DSD64. All DSD content above this is resampled by Roon to DSD64. 

     


    Like all Boulder 866 Closeup.jpgBoulder products, the 866's volume control is purely analog. It's controlled digitally, but at no time is digital attenuation used. Along similar lines, the analog signal, from the three XLR inputs, remains in the analog domain the entire time. The volume control is a design developed by Boulder and improved over many years. The main difference between the 866 volume control and that of the 2000 series products is that the 866 doesn't have fully differential attenuation. The reason for this is  because good analog volume controls cost a lot of money and Boulder needed to decrease the cost of the 866 relative to its higher end products. 

     

    One aspect I found interested, when talking to the Boulder team, was that they learned quite a bit designing this product. Most Boulder products are cost-no-object type of designs that have a completely different set of engineering decisions to make. The 866 Integrated forced the team to get creative and try new things that in the end turned out to be great for the 866 and possibly other Boulder products. Dare I say there could be a trickle-up effect. 

     


    Enjoying the Sound

     

    Listening to my RAAL-requisite SR1a headphones through the Boulder 866 Integrated was a tough job, but somebody had to do it. Only joking of course. This is the part of my job that causes me to thank my lucky stars. I had to listen to the best headphones in the world being driven by a fantastic amplifier, for hours on end. Oh the horror. 

     

    Boulder 866 Wilson Alexia Series 2.jpgGetting right to the point and throwing the 866 Integrated right into the fire, I played Passacaglia from the Kansas City Symphony, recorded by Reference Recordings' Keith Johnson. I encourage everyone to play this track on their systems. Turn the volume up all the way and have a listen. People may not like what they hear on many systems. Through the Boulder 866 Integrated, I heard nothing but incredible detail, noises that were captured on the recording but not part of the performance, and a fantastic string section. This isn't the style of music I usually listen to for pleasure, but I often use it as a laboratory tool to put a components performance on display. Some components wilt on this album and can't handle the incredible dynamic range and detail. The Boulder 866 Integrated sailed through the test, reproducing absolutely everything on this recording without adding anything, even with the volume set to 100 for some passages.

     

    Switching to music that really moves me, I put on Blow Up from the Isao Suzuki Trio recorded for the Three Blind Mice record label. Track one, Aqua Marine, is a delight for the ears with both high and low frequencies that have texture crystal clear qualities. The Boulder 866 Integrated reproduced this tracks on entire album wonderfully. One sonic difference between the 866 and some other amplifiers I've heard in my room is that the 866 sounds a skosh darker on this album, especially when the cymbals are hit fairly hard as opposed to tapped politely. I'm unsure if these specific cymbals are supposed to sound darker or brighter, but the tiny sonic difference is one way to differentiate between the 866 and other components. I can say for certain that the sound is truly terrific, never harsh, and extremely controlled like all other Boulder amplifiers I've heard in the past. No speakers or headphones are going to control a Boulder amplifier, that's for sure. 

     

    Boulder 866 w Speakers 01.jpgIn October 2020, Jewel released a deluxe version of her debut album Pieces of You. My favorite track on the album is the radio edit of Foolish Games. I usually hate radio edits because they remove the good parts in an effort to make a track more palatable for a wider audience, but this version of the Foolish Games is really good. The opening piano and strings on this track are night and day better than the original, and all of it can be heard through the Boulder 866 Integrated / RAAL-requisite SR1a combination. Listening to this version through the Boulder 866 is like listening to a completely different version of Jewel. Her vocals are better and several more instruments can be heard in the background, with air around them. The listener is also able to pinpoint the location of the instruments in the soundstage, while listening through headphones. It's quite an enjoyable experience and an incredible way to listen to old tracks again for the first time. 

     

    I recently listened to Rick Rubin describe his experience producing Tom Petty's Wildflowers album, and was inspired to listen to the new version fo the album called Wildflowers & All The Rest 9Deluxe Edition). I'd forgotten how much I liked this album, especially the track named Honey Bee. It's an album track for sure, but it's one to which I can't stop listening. Through the Boulder 866 / SR1a combination the electric guitar sounds appropriately dirty, grungy and full of fantastic distortion. As both Tom petty and Mike Campbell start and stop / re-enter the track, the little noises before hitting the strings are all audible and bring the listen that much closer to being in the studio. For a recording that I never considered HiFI, I sure enjoyed all that's captured on it and reproduced through this Boulder amp. In fact, Petty's voice at the very start of the track, "All right here we go ..." Sounds so real it's like my headphones are plugged into the soundboard of the recording studio rather than the outputs of the Boulder 866 Integrated. This is what high end audio is all about to me. Bringing me one step, or two steps closer to the real thing. 

     

    866-Front-on-surface-Roon-1200x800.jpg 866-Back-Panel-650x433.jpg

     


     

    Conclusion 

     

    cash@2x.pngMy quest to take the RAAL-requisite SR1a headphones to the next level is off to a fantastic start with the Boulder 866 Integrated amplifier. I selected this unit because it has all the features I need and it's manufacturers and supported by one of the best blue chip companies in all of high end audio. The analog and digital version certainly isn't inexpensive at $14,450, but it's a game-set-match component, just add speakers. The 866 Integrated looks really nice on my desk sitting next to my iMac and my headphone stand. The metal chassis is 100% Boulder, making it impossible to misidentify this amp as that from another company. The fit and finish are second to none. When it comes to sound quality, the main reason we are all into this wonderful hobby, the 866 Integrated is fantastic. 

     

    I wrote at the start of this review that an amp must be fantastic or else I'd hear its flaws through the SR1a headphones. The Boulder 866 delivers the goods flawlessly at all volume levels. I played everything from test tracks (not really fun, but necessary for evaluation) to tracks that grip me emotionally, and the 866 handle them all with ease. Reproducing incredibly wide dynamic range on bombastic symphonic pieces and the very fine details in Jewel Kilcher's voice that bring out the emotion of an 18 year old busker from Homer, Alaska, the Boulder 866 is an all-in-one that can do it all.
     

     

     

     

     

     

    Community Star Ratings and Reviews

     

    I encourage those who have experience with the Boulder 866 Integrated to leave a star rating and quick review on our new Polestar platform.

     

     

     

     

     

    Product Information:

     

     

     

    Associated Music:

     

     

     

    Associated Equipment:

     

     

     

     

    Listening Room:

     

    This graph shows the frequency response of my room before (top) and after (bottom) tuning by Mitch Barnett of Accurate Sound. The standard used for this curve is EBU 3276. This tuning can be used with Roon, JRiver, and other apps that accept convolution filters. When evaluating equipment I use my system with and without this tuning engaged. The signal processing takes place in the digital domain before the audio reaches the DAC, thus enabling me to evaluate the components under review without anything changing the signal further downstream. 

     

    551112741_myroom.jpg.7922adb92cf9efcff4c401f0dffbc5c4.jpg

     

     

     

     



    User Feedback

    Recommended Comments

    The album with Stern/Kansas City Symphony album you mentioned - I believe it's called "Britten's Orchestra" doesn't seem to be available. If anyone knows how to find it - especially a download - let us know. 

    Share this comment


    Link to comment
    Share on other sites
    5 hours ago, VincentvM said:

    Hey Chris, 

     

    Thank you very much for the review, but for me it feels that when reviewing products from firms like Boulder, Tidal, Nagra, DaTtZeel, Goldmund and other companies you are breathing the same rarified air as they are exuding.

    Some audio producties and firms are very established, but not intertersting.

    You pay. You Get. Simple. Safe. Boring.

    I respect the rebranding, but I miss the passion. Yes ,Bentleys are nice to drive now that they're Bavarian, bt the reporting should be about the outside next hot thing.

    Preferably cheap and rediculously overchieving.

    Boulder is neither.

    Please challenge us with outfield discoveries instead and leave you comfort zone.

     

    Kind regards,

    Vincent

    Follower of yours since your first inception, but my account got purged.

    T+A Guy

    Chris is looking for a digital - analog integrated (one box) that's high quality enough for those phones and has all the features he needs. He's also going to review the Parasound, which I believe retails for $3000. So not cheap, but not rarefied air for such an integrated.

    There aren't lots of boxes like that on the market, actually. I guess he could try something like the Mytek or one of the Topping units, but that puts him in the same price neighborhood as the Parasound, so it doesn't really make a huge difference.

    One caveat -  I would be interested to see how a good Class D amp sounds with his phones-it might be a way for some people to get good results for much less money.

    Share this comment


    Link to comment
    Share on other sites
    20 hours ago, firedog said:

    The album with Stern/Kansas City Symphony album you mentioned - I believe it's called "Britten's Orchestra" doesn't seem to be available. If anyone knows how to find it - especially a download - let us know. 

     

    20 hours ago, The Computer Audiophile said:

    Yes, it's the Britten album. I talked to Marcia Martin at Reference Recordings about it a while ago, and she confirmed it is no longer available due to an agreement with the musician's union about how many copies could be sold. Bummer.

     

    Could it be "Britten's Orchestra" sold more copies than anticipated after it won a Grammy award? Maybe the Kansas City Symphony musician's union will make available in some form in the future. Seems a shame to leave it out of print.

     

    Quote

    Prof. Keith O. Johnson and David Frost have received a 2010 Grammy Award!  Category 94 Best Surround Sound Album For vocal or instrumental albums. Albums only.

     

    Share this comment


    Link to comment
    Share on other sites
    2 hours ago, Priaptor said:

    Kudos to Boulder.

     

    Looks to be a great product with a great price sweet spot. Unlike some of the other manufacturers that only produce for the super wealthy it is nice to see Boulder taking charge to provide their great technologies to a much broader audience. 

     

    Beautiful amp, I would definitely consider if looking for an integrated solution.  But at $15K I'm gonna save my salt of the earth accolades for NAD, Schiit, and the like.  

    Share this comment


    Link to comment
    Share on other sites
    On 12/17/2020 at 12:35 PM, PeterG said:

     

    Beautiful amp, I would definitely consider if looking for an integrated solution.  But at $15K I'm gonna save my salt of the earth accolades for NAD, Schiit, and the like.  

    To each his own. My accolades to Boulder was mainly for recognizing a different buyer than their standard products are made for and coming out with a very desirable product that is in reach to many more buyers to enjoy their excellence. While 14K is still lots of money to most, it is a high end ROON endpoint capable DAC, integrated amp offering from one of the most very expensive high end manufactures out there. 

     

    We have seen so many of these uber expensive electronics manufacturers concentrating on products while racing to stratospheric pricing that few if any can afford that I like when I see this. 

    Share this comment


    Link to comment
    Share on other sites

    $15K is an insane amount to pay for audio to most people and enough by itself for an very good complete system, even by audiophile standards. 

    On the other hand, "high end" audio is so high priced these days that $14K for a high quality fully integrated electronics centerpiece - just add speakers- is considered "modestly priced".

    I'm sure this piece is good enough to match with any speakers you'd want - relatively modest or even some that cost several times it's price, so in that narrow sense it is a "bargain". Compare it to some other Boulder stuff and it doesn't seem so high priced. 

    Share this comment


    Link to comment
    Share on other sites
    2 hours ago, firedog said:

    $15K is an insane amount to pay for audio to most people and enough by itself for an very good complete system, even by audiophile standards. 

    On the other hand, "high end" audio is so high priced these days that $14K for a high quality fully integrated electronics centerpiece - just add speakers- is considered "modestly priced".

    I'm sure this piece is good enough to match with any speakers you'd want - relatively modest or even some that cost several times it's price, so in that narrow sense it is a "bargain". Compare it to some other Boulder stuff and it doesn't seem so high priced. 

     

    Agree @firedog.

     

    While I generally don't believe one needs to spend this kind of money on high-fidelity reproduction, as a statement of luxury backed up by a company that has been around >30 years, at $14.5k as a 200Wpc (8-ohm continuous) stereo amp, DAC, and streamer, this looks good...

     

    No way I would consider this a "bargain" but of course it's aimed at a different market segment where the words "bargain" and "value" have a different context than for "Joe Six Pack". :-)

    Share this comment


    Link to comment
    Share on other sites

    Great review. I'm very interested in Boulder 866. How was its internal DAC vs the high-end DACs you have? I'm sure there is a difference, but I wonder how much of difference. Happy Holidays!

    Share this comment


    Link to comment
    Share on other sites
    8 minutes ago, MhtLion said:

    Great review. I'm very interested in Boulder 866. How was its internal DAC vs the high-end DACs you have? I'm sure there is a difference, but I wonder how much of difference. Happy Holidays!

    One area where you can take the 866 performance to another level is using a reference level DAC. For example, I used the Berkeley Audio Design Aloha DAC RS3 with the 866 for testing. It was fantastic, but I brought this amp in because I could use it as an all in one unit. If one wants to improve upon the 866 and price or footprint isn’t an issue, a reference level DAC can do it. 

    Share this comment


    Link to comment
    Share on other sites

    I know that Boulder products have a unique look but, IMO, with the slanted face plate and the "twisted" heat sinks it does kind of look like it got squished in transit. 🙂

    Share this comment


    Link to comment
    Share on other sites
    7 hours ago, Allan F said:

    I know that Boulder products have a unique look but, IMO, with the slanted face plate and the "twisted" heat sinks it does kind of look like it got squished in transit. 🙂

     

    Or overheated and melted...

    Share this comment


    Link to comment
    Share on other sites
    Hello,
     
    I’m very interested in Boulder 866, and found the review.
    - Comparison set up would be Pass Int60 + Bryston BDA 3.14
     
    1) Devialet 
    2) darTZeel LHC-208 
    3) Boulder 866 
     
    My first interest is Boulder 866 because it’s from the US. 
    (I live in the US, so expect to be easy to fix or do something).  
     
    My questions are,
     
    1) How’s your impression? (Especially compared to Pass, Devialet and dartzeel) 
         Not just better/worse, but how’s different?
    2) Do you experience any technical glitch? (In terms of touch screen, wireless integration)
    3) Can you use Apple Airplay? (It’s important to me, I use apple music/idagio and need to stream it.)
    Positive feedback review mentions NO airplay capability but other reviews mention it’s capable. 
     
    I want to solely focus on sound quality since watt is more than enough.
    I strictly listen to Classical music.
     
    Thank you.

    Share this comment


    Link to comment
    Share on other sites

    I  bought a used CODA CSiB (Version 1, 150 watt, Class A first 18) as a headphone amp for the RAAL SR1a. Compared to my Benchmark AHB2 amp it was much better with the RAAL. Compared to the RAAL HSA-1B headphone amp it was almost as good. I am using Audience Conducter SE speaker wire to the RAAL Amp Interface box.

     

    The CODA is shockingly quiet. Almost AHB2 level quiet.

    Share this comment


    Link to comment
    Share on other sites

    I noticed you are also reviewing/testing the Constellation Audio Inspiration Integrated.

    I have a Constellation Audio Inspiration’s Pre-amp 1.0 and Stereo 1.0.  I’m wondering Is moving from the Constellation Inspiration duo to the Boulder 866 a step up, sideways/different, or a step down in sound quality?

    Share this comment


    Link to comment
    Share on other sites


    Create an account or sign in to comment

    You need to be a member in order to leave a comment

    Create an account

    Sign up for a new account in our community. It's easy!

    Register a new account

    Sign in

    Already have an account? Sign in here.

    Sign In Now



×
×
  • Create New...