A novel way to massively improve the SQ of computer audio streaming

[austinpop]

6 hours ago, limniscate said:

I ask May if the SMB connectors negatively affect sound quality.  She said she'll have to test after Munich.

 

4 hours ago, Johnseye said:

 

That she didn't immediately say no, and that they haven't tested this yet is concerning. Convenience at the cost of quality is not worth it in my book when we tweak for the smallest improvements. I'm going to wait then until we know for sure. Thanks for asking. 

 

Great question, and would certainly be good to get clarity.

[austinpop]

BTW - if anyone is going to the Munich High End show, please talk to the SOtM folks in person and get as much info as possible.

[austinpop]

3 minutes ago, Always.Learning said:

Rajiv--

 

It seems you are using a Y cable on the LPS-1 that is powering both the modded switch and the modded sMS-200. Can you tell us where you got the Y cable, how much it cost, and what other options, if any, you considered?

 

Thank you.

 

Sure, happy to.

 

This is the Y-cable: https://www.amazon.com/gp/product/B007Q8IKRE, but I plan to make my own soon using Canare 4S6 as per the DIY cables thread. Just haven't had the time.

 

The other option I considered was to use separate LPS-1s for the switch and the sMS-200. However, upon searching all my cupboards and drawers, I came up one LPS-1 short. Further digging under my sofa cushions for spare change still left me about $393.25 short to buy another LPS-1.

 

[austinpop]

7 minutes ago, Always.Learning said:

 

Ha! Love the humor and the quick response. My next question was going to be whether you thought there might be a sonic improvement with separate LPS-1's powering the switch and sMS-200. And it would appear that your answer is:  I don't know (but if I win the lottery, I'll find out quickly). 

 

I guess the real takeaway is that, despite any potential sonic negatives from using the Y cable, you still heard very significant improvements when adding the switch, and so any additional improvements from using a third LPS-1 in your "Ultra Stack" would just be icing on the cake. 

 

 

Indeed.

 

We did try 3 LPS-1s when I was at @limniscate and it sounded mighty fine!

[austinpop]

1 hour ago, magnuska said:

The question is though if my HD plex is not good enough. I have not heard the previous HD plex 100 w and mine is the upgraded new version they ve jus released.  It sounds actually pretty good. On par with my Teddy pardo.

 

I missed that. I have no experience with the new 200w units, so do not know how they sound.

 

1 hour ago, magnuska said:

Why would you not recommend the 12 v option on the sms Ultra?

 

Simply because it then eliminates the possibility of using it with an LPS-1. You'd be looking at more expensive units like the VR MINI or the Paul Haynes SR5/SR7 to achieve that level of quality or better.

 

The reason SOtM offer the 12v option is not because it is sonically superior, but because it allows you to match to an existing PSU you may already have.

[austinpop]

4 hours ago, magnuska said:

 

Sorry about that! Twas my 1 year old daugther trying to say. Dad I don`t like you sitting so much at the computer. Its my turn now...

 

Adorable! ? ??

[austinpop]

2 hours ago, limniscate said:

Are you sure that the sMS-200 Ultra can be powered by an Uptone LPS-1?  The website says that the max current input is 2A.

 

No I'm not sure. None of us can be, until someone gets their hands on it and tries. 

 

It was just a reasonable extrapolation from the fact that the tX-USBultra in my sytem runs on an LPS-1. 

 

It may well be that the sMS-200 Ultra is just over "the edge."

[austinpop]

My positive experiences with the Ultra stack using a cascade of sCLK reclockings has gotten me to reflect a bit.

 

The three primary factors that I have found to improve the SQ are:

1. Signal integrity - the Ultra stack being the most recent example, but previously experienced via the W4S RUR (Recovery)
2. Leakage loop blockage:
   • from the AC mains via power supplies like the LPS-1
   • on the signal path, via isolators like the Baaske on Ethernet, and the Intona on USB
3. low output impedance on PSUs - again, my direct experience is with the LPS-1, including using Canare star quad DIY DC power cables.

Now - regarding SI (signal integrity) vs. GI (galvanic isolation from leakage loops). The experts at Uptone and SOtM tell us that implementing isolation on the signal path in USB comes at the cost of increased jitter. The ISO-Regen has had a lot of thought and expertise applied to balance these effects. We are all eager to see how this pans out.

 

We don't know whether the same also holds for Ethernet isolators like the EMO EN-70HD, the Etalon, or the iso-CAT6, but it's reasonable to expect so.

 

Having previously had a chain that required an Intona for max SQ, and given the fact that the new Ultra chain degraded when I added in the Intona, it's making me wonder if there is an empirical model emerging from these experiments. Let me be upfront and say - this is just a theory. But here it is in a nutshell:

1. Optimize the data path for maximum signal integrity, by improving the clock quality as far upstream of the DAC as practical
2. Avoid isolators on the signal path to minimize jitter
3. Address the blockage of leakage loops on the power plane, using isolating power supplies - both on the DC side, like the LPS-1, VR Mini, or the Hynes SRn - and on the AC side with Topaz and similar supplies.
4. Minimize the DC PSU output impedance - again by selecting quality PSUs like the LPS-1, VR Mini, or the Hynes SRn

Having said that, @romaz's positive reports with the dCBL-CAT7 and iso-CAT6 seem to contradict #2 above. However, as I remember it, he placed this chain prior to his sCLK-modded switch, so perhaps two factors could explain it:

• all the clocks upstream of the isolator are not optimized (yet)
• the 4 sCLK chain post-isolator sufficiently restores SI, and the iso-CAT6 adds an additional benefit from isolation.

We don't know for sure. 

 

But one of the experiments that will be very interesting will be when Roy adds sCLK mods upstream of the iso-CAT6 in his server. At this point the key comparison will be between the full chain with and without the iso-CAT6 isolator. In other words - if there are superior clocks upstream of the iso-CAT6 isolator, does its presence still improve SQ - or does it degrade SQ?

 

We shall see.

[austinpop]

1 hour ago, romaz said:

 

I will be heading to Munich on Wednesday.  Absolutely, I will have many questions to ask.

 

I'm jealous. I still remember some memorable steins of helles beer, and taking delivery of a car at BMW Welt.

 

And then there's the High-End show. If you have the bandwidth to give us any feedback, it would be greatly appreciated! I'm sure these questions are in your list too, but from my end:

1. Details on their SMB clock connectors
2. details of SOtM switch offering with sCLK-EX 
3. what is their envisioned architecture for sCLK-EX distribution? Is it a separate master clock sCLK-EX box, which can then drive up to 4 slaves using SMB connectors? Or will they continue to co-locate the sCLK-EX in the dX and tX offerings?

 

1 hour ago, romaz said:

 

Rajiv, on the SOtM thread, May has indicated that 12V sounds better.  This is my experience as well with the sMS-200.  I think if you have the option to go 12V, you should do it.  The difference is noticeable.

 

Thanks - I must have missed that. In my email communications with her, she didn't mention that, but that is good to know.

 

12 minutes ago, romaz said:

Where SOtM's sound signature is this wonderful detail clarity, it can also sound a bit thin.  If there has been a criticism with their latest Ultra server, this is it and perhaps, this signature is even intentional.  This is why I value AO with its sound signatures and digital filters because it allows me to put a bit of meat on the bones of the SOtM.  I generally value silver over copper DC cabling but I have intentionally gone with copper with my SOtM gear.  

 

Funny you mention this, Roy. This slight thinness is something I'm noticing too. I am already using AO to tune it. I can get some more warmth by going from 3C to 4D, although I feel that then loses a slight amount of detail.

 

While I just cannot justify the dCBL-CAT7 cost, I will certainly try it when @limniscate's goodies arrive.

 

In the meantime I ordered a Supra Cat8 per your comments to see if I found the same warmth difference with it over the BJC 6a. Will report back.

 

12 minutes ago, romaz said:

Could the Adnaco with its 3 clocks replaced provide the equivalent SQ of Adnaco + tX?  I'm not sure but that would be wonderful.  Is it better than switch + sMS-200Ultra + dX-USB HD Ultra or switch + sMS-200Ultra + tX-USBUltra?  I don't know yet, I'll find out tomorrow but thus far, I can't stop listening.

 

Fascinating, and much awaited!

[austinpop]

21 minutes ago, romaz said:

 

I have tried the F-1 and it is very good but not in the league of any of the Ultra products I have now including SOtM's own USB-to-SPDIF converter, the dX-USB HD Ultra.  Others here have commented that having the SU-1 in the chain following a tX-USBUltra actually results in degradation of SQ.  

 

Real world, for all the people you can name that prefer SPDIF, there are probably many more that are content with or prefer USB.  My experience is that USB is not the problem, its the implementation of the USB that matters and both the DAC and the digital front end that connects to the DAC are equally responsible.

 

Exactly. See @limniscate's and my impressions here: https://www.computeraudiophile.com/forums/topic/30376-a-novel-way-to-massively-improve-the-sq-of-the-sms-200-and-microrendu/?do=findComment&comment=661924

 

Of course, this was not I2S, but AES.

 

[austinpop]

3 hours ago, romaz said:

My dilemma now is whether to stay AOIP and go with switch > sMS-200Ultra > tX-USBultra as Rajiv has done or to take the gamble that a tX-USBultra combined with an Adnaco with better clocks and regulators can equal or perhaps beat this marvelous trifecta.  With the AOIP route, there would be no surprises as I have now heard it.  With the addition of a pair of dCBL-CAT7s, I know it would only get better.  SOtM has told me I could ship back my current combo and they would explant the sCLK-EX clock board from my dX-USB and transplant it into a tX and so I wouldn't have to start from scratch.  Well, I have decided to move forward with the Adnaco mod and compare.  If the Adnaco route fails to be better than the AOIP route, then I will use the Adnaco to connect my music storage drives.  I already know it excels in that capacity.

 

Hi Roy,

 

In these hyper-partisan times, it is good to see you taking a bipartisan, principled approach to this exploration, regardless of ideology!  Whatever that means in Washington, DC, here on CA it means the exploration of clocking while being agnostic to the direct-USB approach vs the distributed networked endpoint approach.

 

I believe one of the reasons your explorations are so fascinating is that very few of us have the option, the inclination, and frankly, the funds to explore both approaches to the extent and with the scientific approach that you are. Kudos, bravo, and thank you!

 

I know I fall strongly in the networked endpoint camp, but you've inspired me to remain open-minded and very curious as to which approach you ultimately prefer.

 

One question in my mind is whether there is an ultimate "best of both worlds" approach that looks something like this:

 

 

Safe travels to Munich, and enjoy the show!

[austinpop]

4 hours ago, tboooe said:

Question to those who have had their switch modded by SOTM.  Will they mod any switch?  I am thinking about having them upgrade my AC Wireless bridge I am using that includes a 4 port switch.

 

https://www.amazon.com/D-Link-Wireless-Gigabit-Extender-DAP-1650/dp/B00JFOP688?th=1

 

Tommy, the best would be to contact May and inquire. They're pretty open to doing mods, but the extent to which they would know ahead of time what's feasible just depends on whether they've had any prior experience with the unit.

 

I sent them a Zyxel GS108Bv3. I really wanted to use a 5-port, but had trouble sourcing it. I was alerted to this switch model by Roy as he recalled it was the baseline Paul Pang used to use. More recently, it looks like Pang and Aqvox are using D-Link DGS-2208 (?) switches, so those may be good to use too. 

 

My main criteria was also to pick a switch whose DC voltage requirements were in the right range and whose power needs were modest, so it could share power from an LPS-1 at 7V with the modded sMS-200.

 

Finally, if you are buying everything else new, it may be possible to ask SOtM to source the switch, so you don't have to ship them anything. I believe @limniscate was pursuing that with them.

[austinpop]

7 hours ago, mozes said:

That would be interesting, my guess is that the Bryston won't have a chance

 

Shame on you! Being a Torontonian, you should be supporting local Canadian companies.

 

[austinpop]

6 minutes ago, Johnseye said:

 

 

I was very tempted to go this route as I already have a 2 rail SR7 build in progress.  Adding a third rail would cause a delay and add cost.  So I asked Paul if he would make a splitter lead.  He said he could but, and I quote him here:

 

"I can build a splitter cable using Switchcraft DC 2.1mm plugs and sockets with fine silver wire. If you let me know the lead lengths for the Y cable sections I can work out a cost for you. However, for the best sound quality, I have to say that I would not recommend powering two items of equipment from one power supply as this will create a ground loop through the DC leads and the equipment interconnect. This will allow the ground return current from both items of equipment to mix and it will cause signal inter-modulation that is usually audible especially on a transparent system."

 

Based on that information I won't be pursuing the splitter option.  Maybe another LPS-1 or a third rail.

 

 

I tend to agree. My solution with a splitter is a stop gap, until I figure out a longer term PSU strategy. Ultimately, my switch will be powered by a separate LPS-1.

[austinpop]

38 minutes ago, guerph said:

Can someone help explain the clock situation? I haven't had time to read through the whole thread. Are there redundant clocks built into the tx-USBultra?? Please dumb it down for me if possible

 

Let me try to net this out.

 

A while ago, SOtM created a clock board, the sCLK-EX, with up to 4 clock outputs (taps), that could be fed to other boards, or external devices. Someone alerted @romaz about the excellent sonics of this clock. I'll let Roy tell the story if he wants, but the net net was that Roy had SOtM create a custom solution for him, comprising the pre-existing dX-USB HD box, modded to house the sCLK-EX board. This was before any official Ultra boxes existed. This "proto dX-USB HD Ultra" consumed one of the 4 taps of the sCLK-EX. The other 3 taps were then sent, using hardwired U.FL cables, to:

1. a modded sMS-200 (consumes 2 taps)
2. a modded Ethernet switch (consumes 1 tap)

I encourage you to go back up thread and find his listening impressions.

 

This is the configuration that Roy reported on, and which inspired me to try to replicate his SQ improvements.

 

By this time, SOtM had revealed their Ultra product roadmap, which comprised 3 distinct devices, each packaging the sCLK-EX board:

1. sMS-200ultra
2. tX-USBultra
3. dX-USB HD Ultra

I had SOtM create the following solution for me:

 

 

I reported on my findings in several posts up-thread:

• https://www.computeraudiophile.com/forums/topic/30376-a-novel-way-to-massively-improve-the-sq-of-the-sms-200-and-microrendu/?do=findComment&comment=659870
• https://www.computeraudiophile.com/forums/topic/30376-a-novel-way-to-massively-improve-the-sq-of-the-sms-200-and-microrendu/?do=findComment&comment=660133
• https://www.computeraudiophile.com/forums/topic/30376-a-novel-way-to-massively-improve-the-sq-of-the-sms-200-and-microrendu/?do=findComment&comment=660539
• https://www.computeraudiophile.com/forums/topic/30376-a-novel-way-to-massively-improve-the-sq-of-the-sms-200-and-microrendu/?do=findComment&comment=661908

We both found maximum SQ benefit by using up all 4 of these clock taps. Roy once called these taps "audio gold," and he wasn't kidding!

 

However, there are price considerations. Each device (swtich, sMS-200, tX-USB) requires a decent PSU, cables etc, so there is a cost to each step. The reason this is somewhat complicated is because the sCLK-EX board can live at different points in the chain, depending on which Ultra box you buy.

 

From a bang-per-buck perspective, I would recommend in this order:

1. sMS-200Ultra. This is the simplest and cleanest options, and gives you a big SQ boost.
2. Next, I'd add the switch, modded to accept an additional sCLK-EX tap from the the Ultra. Either send them one, or have them source it.
3. Finally, the full trifecta, by adding in the tX-USBultra. For this option, I am not sure if you can source a tX-USB HD (regular) and have SOtM mod it to accept the sCLK-EX from the sMS-200Ultra. Remember, I went the opposite route:
   • Start with the tX-USBultra
   • Mod the sMS-200 
   • Mod the switch
4. BTW - others may choose a more expensive but less-fiddly approach by just buying the sMS-200ultra AND the tX-USBultra. Just know that in our experience, we found the modded switch had a profound impact too, which you would be foregoing.

One other thing to consider is shipping cost. If you do this piecemeal, then the shipping of boxes to and back from Korea (at least from the US) can exceed $100 round trip. So if at all possible, I do recommend doing the trifecta in one shot, if it fits your budget.

 

Or you could just wait and see how this shakes out. Frankly, I think SOtM themselves are a bit surprised by our findings, especially with the modded switch.

 

From what May has told me, I would not be surprised to see a more modular solution soon from SOtM, where the sCLK-EX is marketed as a standalone master clock, and they sell sMS, tX, and switches to accept a master clock input.

 

Hopefully we'll learn more from @romaz and others who are in Munich and have a chance to talk directly with May and Lee.

[austinpop]

@romaz

 

Roy, could you also ask if there is jitter introduced by the ISO-Cat6 isolator, and even perhaps the dCBL-Cat7 filters?

[austinpop]

3 hours ago, pam1975 said:

@austinpop which version of the Zyxel router are you using?

 

 

GS108b v3. Switch, not router.

[austinpop]

40 minutes ago, romaz said:

This will effectively be my last post, at least for the foreseeable future.  As I stated previously, after Munich, I am committed to signing off for a while from public forums and I need to honor this commitment and so forgive me if I don't respond to public or private queries for a period of time.  Once my system is complete, I will attempt to resurface to share my findings for those that are interested but that may not happen soon.  I've enjoyed this thread very much.  I hope it continues.  Thank you all for your friendship.

 

I've been busy this weekend with the graduation of my lovely daughter from college, so still have to catch up with a bunch of recent posts. But this caught my eye.

 

Roy, whatever your reasons for this decision, I respect it. When the time is right, please do come back and join us!

 

 

[austinpop]

8 hours ago, limniscate said:

So the TL;DR is get the master clock option on tX/dX and sMS-200, remove regulators, tXUSB Exp may be the best option with external regulator removed?

 

Eric, 

 

This is speculative, but here is what I take away from Roy's remarks on the Mutec and upcoming SOtM master clocks.

 

If, for example, you get a dX Ultra, with the Master Clock input option, AND the mods to clock the swtich and sMS-200 with SMB connectors, then...

1. you would immediately benefit from the trifecta, AND
2. This is the speculative part. Once an even better master clock than the sCLK-EX from Mutec or SOtM is available, you could use this master clock to drive the dX Ultra, and presumably, the benefits of this master clock would flow to the switch and the sMS.

You should confirm this with SOtM.

 

Assuming my understanding is correct, then the extra $200ish for the master clock option may be a worthwhile investment. Of course, it will be a long time before I will be able to justify a $3000+ master clock in my system, but it may make sense to future proof your setup.

 

Until I heard the trifecta in my system, I had never really appreciated the value of excellent clocks.

[austinpop]

34 minutes ago, TopQuark said:

I have the same questions.  If you read the description of the sMS-200Ultra, it comes with sCLK-EX board but with only 2 clocks available all used up by the sMS-200Ultra.  I am verifying this with SOtM so we'll see.

 

I think it's been confirmed that the sMS-200Ultra, like the tX and dX, just includes the sCLK-EX board, which has 4 taps. 2 of these are used internally, and the remaining 2 are available to clock other things.

 

34 minutes ago, TopQuark said:

 

SOtM now offers a new configuration that includes the sMS-200Ultra and the switch mod.  The switch will be sourced by SOtM.  If this is the case, the sMS-200Ultra will include 3 clocks.  This is now available for order at their website.

 

Oh cool. But hmm, I don't see it. Which website? Can you post a link?

 

34 minutes ago, TopQuark said:

 

Still, the question remains whether the sMS-200Ultra board contains 4 clocks or just 3 clocks with the switch mod.  I'll keep everyone posted as I get more info.

 

It's always good to confirm.

[austinpop]

12 hours ago, limniscate said:

So I only need one device to have the external clock option or both?

 

You only would need the master clock input on the Ultra device. This is for the future case where you use an external master clock like the Mutec or future SOtM master clock to improve even further on the sCLK-EX.

 

Regardless of whether you choose the master clock input on the Ultra device, you still need the clock mods, and SMB connections, to send the clock from the Ultra device to other modded devices.

[austinpop]

On 5/12/2017 at 10:59 AM, austinpop said:

Thanks for reminding me to post an update on this.

 

The last experiment May asked me to try was to replace my Ayre Codex DAC with another. Serendipitously, this was the night before my planned listening session at @limniscate's. In over 5 hours of use, briefly with the DAVE, but mostly with the Yggy, I did not have a single pause.

 

So the finger is pointing at an interaction between the tX-USBultra and the Codex.

 

SOtM are in the process of acquiring a loaner Codex from their distributor in Korea to see if they can troubleshoot the problem in-house. I should know more in a few days how that is going. 

 

Yes, I am very satisfied with their level of commitment in resolving this issue.

 

I just wanted to post a quick update that I may have solved the frequent pause issue with my ultra stack.

 

It turns out the culprit was the router in my network. Shortly before I received my Ultra stack back from SOtM, I had a meltdown in my network, where my Arris Surfboard modem stopped working. I was using this in conjunction with an Archer C7 router with no issues in the past. After much troubleshooting, my ISP's tech left me with a leased broadband router from a brand called Technicolor.

 

This was a temporary fix, as I didn't really want a leased router, but in terms of functionality, it seemed perfectly fine, including having the explicit ability to enable UPnP and multicast, which I find are critical for streaming and home automation. What is even odder is that I recently tried this combination:

• switch (sCLK-EX mod) > Aries Mini > tX-USBultra > Codex

and it worked with no pauses at all. But this configuration still had pauses:

• switch (sCLK-EX mod) > sMS-200 (sCLK-EX mod) > tX-USBultra > Codex

Well, today I finally got my replacement broadband modem, a Netgear CM600, and I replaced the Technicolor with the Netgear + Archer C7 combo.

 

No more pauses! 

 

I have been running about 4 hours now without any pause, so I am cautiously optimistic. I will run it overnight to confirm, and update here.

 

Here is my new network topology:

 

 

One final and pleasant note. The Technicolor had a built-in SMPS, which was another annoyance. With the new Netgear, I was able to power it, my router and a switch with a HDPlex 100 in my network closet. In the past, I hadn't really noticed much difference with an LPS this far upstream. Well, now I could. The slight thinness I've been mentioning was substantially gone, and there was just more magic in the music. A very pleasant surprise!

[austinpop]

13 hours ago, austinpop said:

It turns out the culprit was the router in my network.

 

OK great news. My overnight test (playlist in a loop) ran continuously without a single pause, so it is now definitively proven it was my router. For the hall of shame, the exact model of the offending router is:

• Technicolor TC8715D

To be fair, I had no issue with streaming when I replaced the sMS-200 (sCLK-EX mod) with my Aries Mini, so this is a sMS specific issue. I've communicated this to SOtM.

 

Also, even though my previous hypothesis - that the issue was an interaction between the tX and my Codex DAC - proved incorrect, a shout out here to SOtM for outstanding service. May was unable to locate a Codex from the Ayre distributor in Korea, so she talked to the Ayre folks in Munich, and was able to get one of their Codex'es on loan to bring back to Korea to test.

 

10 hours ago, Cornan said:

@austinpop Great to hear that you've solved your annoying issue Rajiv, and on top of that now can enjoy the benefits of further tweaks uphill. Congrats! ?

 

Thanks, Micael! Yes, this glitch was definitely holding back my enjoyment. Since last night, I'm finding myself immersing even more into the music as never before. I guess knowing a pause was coming sooner or later tends to put you on edge!

 

7 hours ago, lmitche said:

Rajiv,

 

If you place a second Baaske back to back with your existing Baaske you are highly likely to gain another step up in SQ.

 

http://www.ebay.com/itm/Baaske-MI-1005-Medical-Ethernet-Isolator-Ferrite-Beaded-RJ45-Isolation-Cable-/142323550095?hash=item212325078f:g:~VUAAOSwCGVX5Vbo

 

Larry, interesting. TBH - I have not found the Baaske to make an audible impact. I have been waiting to borrow or snap up an EN-70HD, Etalon, or iso-Cat6 if it hit the used market, but haven't found one yet.

 

I was actually thinking of moving the Baaske downstream one hop, to sit on the "direct" link from my bridged PC and my modded switch. I'll try it and report back.

[austinpop]

8 minutes ago, ElviaCaprice said:

What I would really like to find out, does adding an ISO Regen between two components clocked with the same s-clk EX clocking board hurt SQ or help?

Also maybe you could test the ISO Regen following the tXusbultra?  Without the tXusb ultra?

   Thanks Mozes.

 

 

That is exactly my question too, and I would love to try that in my setup. Someone want to loan me an ISO-Regen for a couple days? 

 

i know Roy had ordered one, but we won't know his experiences until his return to the forum.

 

I would love to compare this:

• Switch (sClk-EX) > sMS-200 (sClk-EX) > tX-USBultra > DAC, with
• Switch (sClk-EX) > sMS-200 (sClk-EX) > ISO-Regen >  tX-USBultra > DAC
• vary the GI on and off in above 

Note - these configurations need 3 and 4 LPS-1s, respectively, so we may be entering the realm of the surreal soon!

[austinpop]

47 minutes ago, limniscate said:

I ordered a Paul Hynes SR7 DRMR2XL and will compare to my LPS-1.  Embarrassingly though, I have a hard time hearing any differences between my HD-Plex and LPS-1.

 

Being local, my ears are always at your disposal, Eric!

 

What voltage did you get? As I recall, Paul can also do variable voltage if you want him to.