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

[Peter_T]

Oops! Wrong description. It should be this : to update the firmware or to configure to modes other than Roon then the only way is to reset the IP address in the SD card then configure it the normal way then set the IP address again.

This looks interesting : If I decide to go with Roon I probably would start to use ROCK. Two questions

 

1) The way you describe it : this is not an ethernet-bridge between the 2 NIC's on the ROCK computer, but a situation where the SOTM is on a different net segment? In the way I use my NUC with W2016-core (see my post here)

2) In my situation (luckily) I can use firefox under W2016-core to change the SOTM settings. With ROCK you can't. But wouldn't it be easier to unplug the SOTM and plug it into another PC/Notebook in order to change SOTM settings?

[gadgetman]

This looks interesting : If I decide to go with Roon I probably would start to use ROCK. Two questions

 

1) The way you describe it : this is not an ethernet-bridge between the 2 NIC's on the ROCK computer, but a situation where the SOTM is on a different net segment? In the way I use my NUC with W2016-core (see my post here)

 

You are right. It's not a bridge. It's very similar to your setup. The difference is that there's no DHCP running inside ROCK. The IP addresses can be set explicitly. SOtM MUST be on a different net segment.

 

 

2) In my situation (luckily) I can use firefox under W2016-core to change the SOTM settings. With ROCK you can't. But wouldn't it be easier to unplug the SOTM and plug it into another PC/Notebook in order to change SOTM settings?

 

Thank you very much for your advise. Indeed it should be much easier. But the IP address of SOtM still has to be fixed in order for ROCK to recognize it. So one need to setup a private network with the same net segment of SOtM. Then the PC on the net segment can configure it.

[gadgetman]

Deleted for duplicate post.

[gadgetman]

Looks like there are major issues in the alpha version.

 

After playing music for some time (I don't know exactly for how long), that ROCK can loose connection with sMS-200. I'll do more test then report back.

[lmitche]

Hi Larry,

 

I have my equipment list under my profile. I realize it would be better to have it under my signature but because my equipment list seems to be perpetually in flux, I've been too lazy to do it and so I apologize. . . .

 

Hi Romaz,

 

Wow, what a response to my post about approaching CA from opposite corners! Your response is one of best, most articulate and thoughtful posts I've ever seen on CA. We need a posting "hall of fame" button.

 

Instead of opposite corner, perhaps other end of the stick would have been a better analogy. In two years I have bought and sold 4 DACs, and have had 3 long term loaner DACs resident in the $2 to 5k price range.

 

No more, I am currently thrilled with my $550 IFI Black Label DAC playing hqplayer upsampled everything at DSD512.

 

Why? I concluded that SQ is so profoundly influenced by the PC hardware and software environment that until the PC environment was stable and sounding its best there was no way to truly validate the difference in quality of various DACs in any price range.

 

Think about the past year or so. It has only been since last January that Intel chips have been available that have the performance needed to crunch DSD512. Groundbreaking devices like the LPS-1 are only available since October 2016. Roon is less than a year old. We have seen major releases of operating systems, AO and HQplayer in the same timeframes. This is a quickly moving field and until it slows, it is tough for me to justify a major investment in a technology that could be made obsolete so quickly. So, I choose to use commodity components for my digital front end, including my DAC.

 

My analog side is Wilson and Modwright and as speaker and amplification technologies are well understood and stable the investment is easy to research and justify.

 

Sadly, someday we will see the bottom of the bottomless pit known as ComputerAudiophile sound quality. But for now I am just amazed that the innovations keep coming and that the SQ gets better and better.

 

Lastly no need to apologise for not posting your configuration. I never have.

 

Thanks again for your wonderful post.

[ElviaCaprice]

Larry, thanks for your input concerning upsampling with HQP. I have fought over the notion of going this route instead of bit perfect, but every time I think it through, I pause, and finally give up on the notion. My concerns, other than lack of functionality with HQP, like library and video, is that by making the first part of the streamer process such a noisy high powered component, that one is doomed from the get go injecting noise into the USB stream. How do you find this balance between the advantages of HQP upsampling/filtering over the noisy high power needed?

 

Also, I would think that because of the noisy PC, one would definitely need an NAA or renderer to try and mitigate those initial negative effects? And that brings up another host of possible issues?

[romaz]

Hi Romaz,

 

Wow, what a response to my post about approaching CA from opposite corners! Your response is one of best, most articulate and thoughtful posts I've ever seen on CA. We need a posting "hall of fame" button.

 

Instead of opposite corner, perhaps other end of the stick would have been a better analogy. In two years I have bought and sold 4 DACs, and have had 3 long term loaner DACs resident in the $2 to 5k price range.

 

No more, I am currently thrilled with my $550 IFI Black Label DAC playing hqplayer upsampled everything at DSD512.

 

Why? I concluded that SQ is so profoundly influenced by the PC hardware and software environment that until the PC environment was stable and sounding its best there was no way to truly validate the difference in quality of various DACs in any price range.

 

Think about the past year or so. It has only been since last January that Intel chips have been available that have the performance needed to crunch DSD512. Groundbreaking devices like the LPS-1 are only available since October 2016. Roon is less than a year old. We have seen major releases of operating systems, AO and HQplayer in the same timeframes. This is a quickly moving field and until it slows, it is tough for me to justify a major investment in a technology that could be made obsolete so quickly. So, I choose to use commodity components for my digital front end, including my DAC.

 

My analog side is Wilson and Modwright and as speaker and amplification technologies are well understood and stable the investment is easy to research and justify.

 

Sadly, someday we will see the bottom of the bottomless pit known as ComputerAudiophile sound quality. But for now I am just amazed that the innovations keep coming and that the SQ gets better and better.

 

Lastly no need to apologise for not posting your configuration. I never have.

 

Thanks again for your wonderful post.

Thank you, Larry. Over the years, as I have scoured the forums for much-needed information, I frequently came across your posts (including your posts on bridging LAN ports a few years back) and I always found them to be well-reasoned, balanced and insightful. Much respect.

 

What you say about digital is very true. While I have a firm grasp of the analog side of my chain, I don't feel that way about digital. It's just evolving so quickly. Just when I think I have everything figured out, something new comes out from nowhere and I find myself having to recalibrate my thinking. If you could only see the stockpile of digital gear and parts I have lying around, it's quite depressing, but once you hear how much better the new thing is, it's hard to unhear what you've heard. Hopefully, one day soon, I'll learn to be content with what I have but for now, I am quite amazed how simple and small changes have lead to fairly profound improvements and so it's hard to want to get off the bus just yet. There is one observation that has become quite clear, however, and that is it makes no sense to spend huge money on digital these days. Things get obsolete much too quickly and technology quickly trickles down. I believe you are wise to let the dust settle before making big changes. Now, if only I could learn the same lesson...

[gadgetman]

ROCK is much more stable now. I've been running ROCK for more than 10 hours and it's still working fine. No more connection lost though there still is small glitches.

 

Current version is build 206. I remember it was build 204 at the time I installed it. Perhaps the bug was fixed in new build.

 

Hopefully I'll be able to do the SQ comparison this weekend.

[lmitche]

Larry, thanks for your input concerning upsampling with HQP. I have fought over the notion of going this route instead of bit perfect, but every time I think it through, I pause, and finally give up on the notion. My concerns, other than lack of functionality with HQP, like library and video, is that by making the first part of the streamer process such a noisy high powered component, that one is doomed from the get go injecting noise into the USB stream. How do you find this balance between the advantages of HQP upsampling/filtering over the noisy high power needed?

 

Also, I would think that because of the noisy PC, one would definitely need an NAA or renderer to try and mitigate those initial negative effects? And that brings up another host of possible issues?

Hi Elvia,

 

I agree, there needs to be two galvanically isolated zones for good SQ, one for the upsampling PC, the other for USB input to the DAC. Over here using the Adnaco USB fiber solution, the fiber separates the atx power supply, CPU, memory, motherboard and hard disk from the USB signal. The fiber to copper conversion happens on the other side of the fiber in a low current device powered by an LPS1.

 

So it's kinda like the NAA design idea, with less processing and noise in the DAC side gear.

 

Also, if I have it right, this same design idea will also be possible with the new ISO REGEN product from Uptone which I look forward to hearing.

 

Despite the galvanic isolation between the PC and USB sides, my recent tweak of replacing the SSD with a hard disk for boot and music storage had a surprisingly positive impact on sound quality. Think of those situations where you are between two mirrors and the image disappears into the vanishing point.

 

https://www.google.com/search?q=mirror+into+mirror&client=tablet-android-lenovo&prmd=isvn&source=lnms&tbm=isch&sa=X&ved=0ahUKEwi3zbb787fSAhUF4oMKHb4SBHEQ_AUIBygB&biw=800&bih=1280#tbm=isch&q=mirror+into+mirror+reflection&*&imgrc=Qbu1Y3yEIXmoJM:

 

Replacing the SSD creates a "one mirror" level of clarity that is rather jaw dropping in the level of presence and sense of being in the room with the performers. I hear a lot of live music, and can finally hear the room in its entirety which is especially exciting on live performances.

 

Clearly local music retrieval without the network in combination with reduced EMI from the SSD delivers this result.

 

This is all with HQplayer, so pretty good for a non-bit-perfect approach.

 

I hope this answers your question.

[ElviaCaprice]

Hi Elvia,

 

I agree, there needs to be two galvanically isolated zones for good SQ, one for the upsampling PC, the other for USB input to the DAC. Over here using the Adnaco USB fiber solution, the fiber separates the atx power supply, CPU, memory, motherboard and hard disk from the USB signal. The fiber to copper conversion happens on the other side of the fiber in a low current device powered by an LPS1.

 

So it's kinda like the NAA design idea, with less processing and noise in the DAC side gear.

 

Also, if I have it right, this same design idea will also be possible with the new ISO REGEN product from Uptone which I look forward to hearing.

 

Despite the galvanic isolation between the PC and USB sides, my recent tweak of replacing the SSD with a hard disk for boot and music storage had a surprisingly positive impact on sound quality. Think of those situations where you are between two mirrors and the image disappears into the vanishing point.

 

https://www.google.com/search?q=mirror+into+mirror&client=tablet-android-lenovo&prmd=isvn&source=lnms&tbm=isch&sa=X&ved=0ahUKEwi3zbb787fSAhUF4oMKHb4SBHEQ_AUIBygB&biw=800&bih=1280#tbm=isch&q=mirror+into+mirror+reflection&*&imgrc=Qbu1Y3yEIXmoJM:

 

Replacing the SSD creates a "one mirror" level of clarity that is rather jaw dropping in the level of presence and sense of being in the room with the performers. I hear a lot of live music, and can finally hear the room in its entirety which is especially exciting on live performances.

 

Clearly local music retrieval without the network in combination with reduced EMI from the SSD delivers this result.

 

This is all with HQplayer, so pretty good for a non-bit-perfect approach.

 

I hope this answers your question.

Thanks Larry,

I can't help but find this result after your care for galvanic isolation with the Adnaco (I take it this is the one your using, Adnaco-S3B?), a bit troubling? Makes me wonder how much more positive effect your main PC would have instead under a low power, pico-itx mobo powered by a great LPS? Obviously one would have to drop the upsampling HQP?

Again, to upsample filter before the DAC, noisy? or within the DAC but under an isolated low powering system?

[lmitche]

Elvis, I am not sure why you say troubling. The PC is probably drawing less than 1 amp at 120 volts in full operation, so not exactly high power. SQ is just excellent. I guess I miss your point.

[romaz]

Bad clock > Better clock > Best clock

My second LPS-1 arrived today and I found myself with new found flexibility to try some different things while I await parts for my upcoming build to come in.

 

As many know, aside from this Trend Net switch that I sent in to SOtM to have its clock replaced with the sCLK-EX, I also own a Paul Pang switch with TCXO clock. As previously reported, this Trend Net with its upgraded clock readily improved upon the Paul Pang switch by a considerable margin. Since the arrival of the sCKL-EX, this Paul Pang switch has been sitting idle. With the aid of my new LPS-1, I decided to reintroduce this switch back into the "direct connection" pathway. Here is what I compared:

 

Here is my baseline setup: Mac Mini > Trend Net switch with sCLK (LPS-1) > sMS-200 Ultra (LPS-1) > dX-USB HD Ultra (SR7) >DAC

 

Configuration (1): Mac Mini > Paul Pang switch with TCXO (LPS-1) > Trend Net switch with sCLK-EX (LPS-1) > sMS-200 Ultra (LPS-1)...

Configuration (2): Mac Mini > Trend Net switch with sCLK-EX (LPS-1) > Paul Pang switch with TCXO (LPS-1) > sMS-200 Ultra (LPS-1)...

 

Once again, I have already established that the sCLK-EX is a much better clock than the TCXO. At the present time, my Mac Mini has stock clocks.

 

Findings:

 

Configuration 1:

This configuration goes from bad clock to better clock to best clock. Compared against my baseline setup, the addition of the Paul Pang switch with TCXO clock positioned before the Trend Net switch and with both powered by my new LPS-1 very nicely resulted in further improvement in SQ. It wasn't a giant improvement but was easily noticeable. Bass was stronger, separation was better, transients were cleaner, guitar plucks had a crisper staccato...nothing bad, all good. By now, I guess I shouldn't be surprised but yet I am.

 

Configuration 2:

This configuration now goes from bad clock to best clock to intermediate clock. Compared against Configuration 1, SQ for sure takes a hit. It still sounds good but there is an obvious diminishment in dynamics. Transients are slightly more diffuse and the guitar staccato is noticeably softer. Compared against baseline, it's a close call. I will need to do further listening and will probably need to blind test to convince myself but my initial inclination is that it sounds just slightly more compressed compared against baseline suggesting that this switch has now actually caused harm.

 

Just for kicks, I proceeded with a Configuration 3 even though I was pretty sure I knew what would happen.

 

Configuration 3: Mac Mini > Paul Pang (LPS-1) > Trend Net (LPS-1) > NETGEAR GS108TV2 with stock switching PSU > sMS-200 Ultra..

 

I use this Netgear switch in my home theater. It has no special clocks and as noted above, I used its stock 12V switching PSU to power it because it's all I had. Not surprisingly, there is an obvious harshness that is introduced and dynamics and liquidity are significantly compromised. No bueno.

 

CONCLUSIONS: I had previously postulated that a bad clock that follows a good clock has the potential to negate the good clock. These findings would support that theory. Without a doubt, it's best to put your best clock at the end and to avoid all bad clocks whenever possible. Once again, I am surprised that further reclocking (with good clocks) results in better and better SQ but my guess is that with each reclocking, there has to be some diminishing return. I am more optimistic now than before that replacing all pertinent clocks in my upcoming build will result in further improvement in SQ.

[spartan1969]

What I do believe this "direct connection" has brought besides increased resolution, clarity and immediacy that Mark Jenkins talks about is transparency to upstream components which is both a good thing and a bad thing. For those of us who apply proper care and attention to our upstream components, we are rewarded for our efforts and for those of us who don't, there are sonic penalties. [/size]

 

Hi Romaz,

Can you please explain what precisely do you mean by the passage in quotes here?

 

More specifically to file storage, what is giving you the best results now. The SATA adaptor to SDcards you mentioned is interesting. Did you suggest that SD cards are a better solution for storage (in terms of SQ) than the alternatives? That has been my suspicion too. If so, is there a way, or adaptor, you have tried, that allows us to use extra SD cards (other than, of course, the SD card used for the system) for storage?

 

I'm too having a very fine SQ with the MacMini booted from SDcard with El Capitain. Moreover, I'm using a mac-to-mac connection as suggested by Superdad a few years ago. Also, my macmini is already on the best PS I can think of and I'm using Roon.

 

All those "extra things" you're using (microrendu, sms200, clocks, switch, USBoptimizer, and respective supplies) can become very expensive and a small nightmare in terms of space, cables, etc. Pardon me if I hesitate a bit... but it's a potential mess, as you'll probably agree. I have read this entire thread and one would be silly not to believe your findings, as they are very well explained and documented. But if you compare the macmini-sdcard system (the one I'm using) with that same system plus all the extras in question (apparently what you are using), do you think now it really pays off? In other words, unplug all those "extra" supplies from the wall (remove all the "extras" from the room if possible) and play the mini for a while. Now connect all the extras and listen. What happens?

 

I'm asking this apparently redundant question because a few post ahead you said you have returned to the sdcard with elcapitain with great relief. And sometimes we travel great lengths looking for improvement to realize much later that what we had before was better. Was that (at least partially) the case?

 

By the way, what OS system are you planning to use in your future server (nice project!)

 

Thanks,

Spartan

[Theobetley]

Hi Romaz,

Can you please explain what precisely do you mean by the passage in quotes here?

 

More specifically to file storage, what is giving you the best results now. The SATA adaptor to SDcards you mentioned is interesting. Did you suggest that SD cards are a better solution for storage (in terms of SQ) than the alternatives? That has been my suspicion too. If so, is there a way, or adaptor, you have tried, that allows us to use extra SD cards (other than, of course, the SD card used for the system) for storage?

 

I'm too having a very fine SQ with the MacMini booted from SDcard with El Capitain. Moreover, I'm using a mac-to-mac connection as suggested by Superdad a few years ago. Also, my macmini is already on the best PS I can think of and I'm using Roon.

 

All those "extra things" you're using (microrendu, sms200, clocks, switch, USBoptimizer, and respective supplies) can become very expensive and a small nightmare in terms of space, cables, etc. Pardon me if I hesitate a bit... but it's a potential mess, as you'll probably agree. I have read this entire thread and one would be silly not to believe your findings, as they are very well explained and documented. But if you compare the macmini-sdcard system (the one I'm using) with that same system plus all the extras in question (apparently what you are using), do you think now it really pays off? In other words, unplug all those "extra" supplies from the wall (remove all the "extras" from the room if possible) and play the mini for a while. Now connect all the extras and listen. What happens?

 

I'm asking this apparently redundant question because a few post ahead you said you have returned to the sdcard with elcapitain with great relief. And sometimes we travel great lengths looking for improvement to realize much later that what we had before was better. Was that (at least partially) the case?

 

By the way, what OS system are you planning to use in your future server (nice project!)

 

Thanks,

Spartan

I am not Romaz but I can guarantee you if you go 'direct connection' you will have to reevaluate all your tweaks all over again. Before 'direct' I had a Baaske filter and FMCboxes connected with fiber optic cables that all came out because 'direct' sounded better without them. When I first went 'direct' I left all those things in and it sounded way better than before. Taking out all the stuff made things even better. You will not be disappointed with direct connection.

[spartan1969]

Thanks. Can you just explain what you mean by "direct connection"? Maybe I'm missing the terms here...

[lmitche]

Thanks. Can you just explain what you mean by "direct connection"? Maybe I'm missing the terms here...

Spartan, direct connection means running a wired connection between a NAS or upsampling machine and a rendering machine running MPD, NAA, Roon endpoint, etc . . . WITHOUT use of a ethernet switch or router. In other words just a straight wire, or two straight wires with a passive isolation transformer between the two machines. This implies that the middle machine run two NICs, with the first connected to the machine described above, the second to an internet connection and the rest of the local network.

 

There are currently two ways to accomplish this, the first is to create a virtual switch with port bridging, and the second is to run a DHCP server on the middle machine for the endpoint.

 

All of this is described in the pages above.

[spartan1969]

You must mean without having the router as the hub, right? The router is still connected somewhere I presume...

 

I believe that's what I have here: two computers connected through ethernet. But one of them connects to the router (otherwise, how do you have streaming service?), the other is the end computer with the sdcard.

 

In any case, I was not asking about the term "direct connection", but the rest of the quote : "For those of us who apply proper care and attention to our upstream components, we are rewarded for our efforts and for those of us who don't, there are sonic penalties. "

[tboooe]

 

Here is my baseline setup: Mac Mini > Trend Net switch with sCLK (LPS-1) > sMS-200 Ultra (LPS-1) > dX-USB HD Ultra (SR7) >DAC

 

Configuration (1): Mac Mini > Paul Pang switch with TCXO (LPS-1) > Trend Net switch with sCLK-EX (LPS-1) > sMS-200 Ultra (LPS-1)...

Configuration (2): Mac Mini > Trend Net switch with sCLK-EX (LPS-1) > Paul Pang switch with TCXO (LPS-1) > sMS-200 Ultra (LPS-1)...

 

@romaz just to be clear, in your base configuration are you still using a direct connection between mac mini and sms-200? From what you wrote it looks like the mac mini and sms-200 are both connected to the Trendnet?

[lmitche]

You must mean without having the router as the hub, right? The router is still connected somewhere I presume...

 

I believe that's what I have here: two computers connected through ethernet. But one of them connects to the router (otherwise, how do you have streaming service?), the other is the end computer with the sdcard.

 

In any case, I was not asking about the term "direct connection", but the rest of the quote : "For those of us who apply proper care and attention to our upstream components, we are rewarded for our efforts and for those of us who don't, there are sonic penalties. "

 

Spartan, I thought when you posted,

 

'Can you just explain what you mean by "direct connection"' post #890 above,

 

you were asking about the definition of "direct connection".

 

Apologies for wasting your time.

[spartan1969]

Spartan, I thought when you posted,

 

'Can you just explain what you mean by "direct connection"' post #890 above,

 

you were asking about the definition of "direct connection".

 

Apologies for wasting your time.

 

 

oh, thanks for the help... but did you read my first post?

[austinpop]

Bad clock > Better clock > Best clock

<snip>

 

CONCLUSIONS: I had previously postulated that a bad clock that follows a good clock has the potential to negate the good clock. These findings would support that theory. Without a doubt, it's best to put your best clock at the end and to avoid all bad clocks whenever possible. Once again, I am surprised that further reclocking (with good clocks) results in better and better SQ but my guess is that with each reclocking, there has to be some diminishing return. I am more optimistic now than before that replacing all pertinent clocks in my upcoming build will result in further improvement in SQ.

 

Hi Roy,

 

Very interesting experiments! I really appreciate your empirical approach to the hypothesis of end-to-end clock quality.

 

I have some thoughts and a request for a couple of additional experiments, if you'll indulge me!

 

Thoughts:

 

• In terms of clock quality, I see your baseline configuration of:
  
  • Mac Mini > Trend Net switch with sCLK (LPS-1) > sMS-200 Ultra (LPS-1) > dX-USB HD Ultra (SR7) >DAC
    
  • In terms of clocks: Bad > Best > Best > Best > World class (DAVE)
    

   

  [*]Your config 1, in terms of clocks, was: Bad > Better > Best > Best > Best > World class

  • It is still amazing to me that the addition of a better clock upstream of 3 existing "best" clocks still resulted in an SQ boost!
    
  • I assume this is why you tried it, but the Paul Pang switch in config 1 is a "proxy" for your new system build with better clocks. So this was a good PoC (proof of concept). Well done!
    

   

  [*]I do wonder how much of the sensitivity to superior clocks is dependent on the inherent quality of the DAC's clocks. Your DAVE is obviously in a rarefied category, as it should be, at the price. What I wonder is if this phenomenon would hold true with more modest DACs.

   

   

  [*]Finally, I wonder whether the upgraded clock and LPS-1 on your Trendnet switch might render the "direct connection" mod moot? I'll elaborate in the experiments I propose for you below.

Suggested (requested) Experiments:

 

1. Do you have any lower-end DAC on hand to test your clock sensitivity experiment? It would be very interesting to know if even with DACs in the sub-1k or sub-2k range, your clock sensitivity still holds. My gut says it should.
    
    
   
2. With the superior clocking in place on your switch, go back to a switched instead of direct connection.
   
   • Compare your baseline: Router > Mac Mini > Trend Net switch with sCLK (LPS-1) > sMS-200 Ultra (LPS-1) > dX-USB HD Ultra (SR7) >DAC with:
     
   • configuration 4:
     
     • Mac Mini > Trend Net switch with sCLK (LPS-1) > sMS-200 Ultra (LPS-1) > dX-USB HD Ultra (SR7) >DAC
       
     • Router > Trend Net switch with sCLK (LPS-1)
       

Hope this makes sense.

[romaz]

Hi Romaz,

Can you please explain what precisely do you mean by the passage in quotes here?

 

More specifically to file storage, what is giving you the best results now. The SATA adaptor to SDcards you mentioned is interesting. Did you suggest that SD cards are a better solution for storage (in terms of SQ) than the alternatives? That has been my suspicion too...

 

I'm too having a very fine SQ with the MacMini booted from SDcard with El Capitain. Moreover, I'm using a mac-to-mac connection as suggested by Superdad a few years ago. Also, my macmini is already on the best PS I can think of and I'm using Roon.

 

All those "extra things" you're using (microrendu, sms200, clocks, switch, USBoptimizer, and respective supplies) can become very expensive and a small nightmare in terms of space, cables, etc. Pardon me if I hesitate a bit... but it's a potential mess, as you'll probably agree. I have read this entire thread and one would be silly not to believe your findings, as they are very well explained and documented. But if you compare the macmini-sdcard system (the one I'm using) with that same system plus all the extras in question (apparently what you are using), do you think now it really pays off? In other words, unplug all those "extra" supplies from the wall (remove all the "extras" from the room if possible) and play the mini for a while. Now connect all the extras and listen. What happens?

 

Hi Spartan,

 

You raise very good questions. You have an excellent setup already and so as always, if you are happy with the SQ you are getting, there's no reason to do anything further.

 

As to whether a highly optimized Mac Mini setup such as yours can be improved upon by something like the mR or sMS-200, my answer is yes, absolutely. My Mac Mini setup isn't that different from yours. I am using Uptone Audio's excellent MMK just like you are which allows me to power it with my Paul Hynes SR7, the finest PSU I have personally experienced. Presently, I am running an optimized version of El Capitan off of an SD card just like you are. I understand you are using Alex's Mac-to-Mac connection method to access your music files and I have no doubt that this sounds better than streaming from a NAS but thus far, my best SQ is playback from an SD card using a Thunderbolt SD card reader from Sonnet Tech and I suspect this method of playback is at least as good as your Mac-to-Mac direct connection. Having tested and compared this further just this evening, it is superior to playback from an SSD or hard drive even though my SSD and hard drive were each powered by an LPS-1 during my comparisons. The difference isn't as prominent compared against the OS off the SD card vs the OS off an SSD or hard drive but there is definitely a quieter and less stressed quality to music playback when files are stored on an SD card which is to my preference.

 

Despite all of these optimizations, I cannot get my Mac Mini by itself to sound anywhere as good as when my Mac Mini is fronted by either the mR or sMS-200 via this direct connection. Here are some reasons why I believe this is the case:

 

1. Clocks. This is an obvious topic of interest for me right now given how dramatic the differences I am hearing with a really good clock against a bad clock. Having torn apart my second Mac Mini recently, I was able to identify at least 2 clocks that I could replace with SOtM's new sCLK-EX if I decided to stick with my Mac Mini and that would be the system clock and the LAN clock. If I chose to replace these bad clocks with SOtM's new superclock, without question, I would power this SOtM clock board with a 12V lead from another SR7 that I have on order because I have found that the quality of power to the clock to be extremely important. Now here's the problem with the Mac Mini or any PC that you can build today that utilizes any of the off-the-shelf motherboards that are commercially available. Even if I replace the main system clock (24MHz), there are many subsystems within the motherboard (SATA, USB, PCIE, video card, audio card, etc) that require independent clocking but do not operate at the 24MHz frequency of the main system clock and so what happens is that these subsystems derive their timing from sub-clocks (DPLL) that use the main clock as a master clock. Is this as good as having separate master clocks for each subsystem? No, it's a compromise but moreover, guess how these DPLLs are powered? By noisy switching regulators that all off-the-shelf motherboards utilize. With either an mR or sMS-200, much higher quality clocks are used and these clocks are powered by ultra low noise linear regulators.

 

2. Ground plane noise. In the Mac Mini or any PC, this will come from many sources including numerous switching voltage regulators, a current-hungry CPU, RAM, internal storage, various unnecessary ICs, and potentially the power supply. While the current draw of your optimized Mac Mini is pretty low compared to other PCs, it still will be higher compared against the mR or sMS-200. Powered by a 9V supply, the sMS-200 draws well below 0.5A. Powered by a 12V supply, the draw is even less and this is how I prefer to power the sMS-200 because it sounds even better this way. The point is this is why Roon strongly advocates an ethernet connection between a noisy server and a much quieter Roon endpoint because ethernet is inherently galvanically isolated and would help isolate some of this noise.

 

3. Heavy OS. Despite my efforts to optimize El Capitan, I was never able to get it to be as light weight (and therefore sound as good) as Windows with Audiophile Optimizer. The Linux OS used by either the mR or sMS-200 (which also runs off an SD card) is even lighter weight.

 

4. Impedance. The Mac Mini (or NUC) has a nice compact form factor with short signal paths but the signal paths in either the mR or sMS-200 are even shorter. Furthermore, the very fine PSU you are using to power your Mac Mini will likely not have as low an output impedance as an LPS-1 that you could use to power either an mR or sMS-200.

 

5. USB. The best way to do USB is to use a dedicated USB card (such as from SOtM or Paul Pang) with it's own high quality clock (not DPLL) and independently powered by a high quality linear PSU. This isn't possible with a Mac Mini or NUC as they have no free PCIe slots and even if it was, these USB cards don't offer galvanic isolation like ethernet does. You could use an Intona or Adnaco but to be on par with an mR or sMS-200, you would need to replace the bad clocks in these devices and even then, there's no guarantee. SOtM has apparently explored the Intona and found this device to create considerable jitter that has as much to do with the chipset used and not just a substandard clock. Of course, the soon-to-be-released Iso Regen by Uptone Audio could be the X-factor and could very well alter the landscape once again.

 

 

I'm asking this apparently redundant question because a few post ahead you said you have returned to the sdcard with elcapitain with great relief. And sometimes we travel great lengths looking for improvement to realize much later that what we had before was better. Was that (at least partially) the case?

 

By the way, what OS system are you planning to use in your future server (nice project!)

I have to say that to be able to run the OS off an SD card is huge and it is one reason I much prefer the Mac Mini to a NUC. This concept has been promoted by Paul Pang for years and with a build that I ultimately scrapped 2 years ago, I was going to use Paul's CF to SATA adapter which also incorporated his OCXO clock for my OS. And yes, it is my experience that the OS drive has a greater impact on SQ than the music drive.

 

My only problem with running El Capitan off an SD card was that despite my best efforts to optimize it, I could never get below about 115 open processes whereas with Windows, you can get down to 15-20 open processes. I thought quite possibly that an optimized Windows OS off a PCIE SSD could sound better than El Capitan off an SD card. What I found was that it both sounded better and worse. The PCIE SSD definitely added an unpleasant fatiguing harshness but Windows Server 2012R2 + AO + Process Lasso was without question a better OS than El Capitan and furthermore, I found the sound signature/digital filter options that come with AO to be invaluable. If there was a way to run Windows off an SD card in the Mac Mini, my problems would be solved but thus far, I have not figured out how to do this and neither have my IT friends at Apple.

 

With my upcoming server build, I will compare what I can and am open minded to whatever sounds best but as of now, the best OS I have heard with Roon is Window Server 2012R2 + AO in minimal server mode + Process Lasso. I am determined to run this OS off a 64GB SLC compact flash card using the following device:

 

https://www.amazon.com/gp/product/B0030D3T16/ref=ox_sc_act_title_1?ie=UTF8&psc=1&smid=A324BLMM6O8TAP

Unlike the Mac Mini, I will be able to power this adapter and my compact flash card using an LPS-1. It also has a clock that potentially can be replaced.

 

...is there a way, or adaptor, you have tried, that allows us to use extra SD cards (other than, of course, the SD card used for the system) for storage?

 

As you have suggested, the downside of SD card storage is limited space. They presently get as large as 512GB although 1TB SDXC cards have been announced by SanDisk and SDXC has the potential to reach 2TB. I have ordered these SD-to-SATA devices to try out although I don't know how good they will be. One device can hold 4 SDXC cards and the other can hold 10 microSD cards (up to 1.28TB of storage) and either device can be independently powered by an LPS-1.

 

4 SD SDHC SDXC MMC TF Card to SATA 2.5" SSD enclosure Adapter RAID Function WP | eBay

 

10x Micro SD TF Memory Card to SATA SSD Adapter RAID Quad 2.5" SATA Converter | eBay

[romaz]

In any case, I was not asking about the term "direct connection", but the rest of the quote : "For those of us who apply proper care and attention to our upstream components, we are rewarded for our efforts and for those of us who don't, there are sonic penalties. "

 

What I have found this "direct connection" between music server and endpoint to result in is a greater transparency not just to the recording but also to the upstream components which can be both a good thing and a bad thing. With either the mR or sMS-200 directly connected to the router, it matters far less how good (or bad) the server is. Without the router in the direct path, suddenly bad sources sound bad and good sources sound good. With this direct connection, things like an optimized OS, less noisy storage and a better power supply to the server make much more of a difference.

[romaz]

@romaz just to be clear, in your base configuration are you still using a direct connection between mac mini and sms-200? From what you wrote it looks like the mac mini and sms-200 are both connected to the Trendnet?

Yes, when I say "direct connection," I mean that the router is no longer in the path between server and endpoint. With respect to the Trendnet, it is indeed in the direct path. Without a decent clock and powered by a switching PSU, a switch in the direct path definitely negatively impacts SQ. With respect to the Trendnet which has had its clock replaced by SOtM's superclock and is powered by an LPS-1, it significantly improves SQ.

[romaz]

 

It is still amazing to me that the addition of a better clock upstream of 3 existing "best" clocks still resulted in an SQ boost!

 

I agree, Rajiv. I am surprised as well and this is the best way I know to explain it:

 

The best signal you can have is the original unfettered, unadulterated signal but as this signal goes through the signal path, it goes through repeated processing and reprocessing and with each processing, that signal must be regenerated and reclocked. When the signal from your ISP enters your internet modem, it is processed. It is processed again when the data is converted into an ethernet stream and again with every switch or FMC it encounters and again when that stream reaches your server's LAN port, and when it hits your system bus, and when it is rendered by your CPU and so on and so on. With ever regeneration and reclocking of the signal, there is potential for the signal to be harmed through the introduction of jitter through poor clocking and the introduction of substrate noise that is likely to be additive as the signal moves through the chain.

 

While this is pure conjecture, my experience would suggest that placement of a clean and accurate clock in the signal path has the potential to clean up and even repair some of the harm that has been caused but if the harm already done is significant, a single reclocking may only be able to improve it so much. A good analogy might be running a fairly clean car through a car wash vs running an off-road vehicle with caked on mud and tar through that same car wash. It may take several car washes before the off-road vehicle gets thoroughly cleaned and even with multiple washings, it may not be possible to completely clean it. This is why I have suggested that it would probably be best to avoid bad things in the signal path early on rather than having to add heroic (and expensive) fixes at the end.

 

What I wonder is if this phenomenon would hold true with more modest DACs.

 

My guess is that if your system (which would include not just your DAC but also your amp, speakers and cables) is resolving enough to reveal the benefits of this direct connection, it is probably resolving enough to reveal the benefits of better clocking. While I suspect there is more to this direct connection than just avoiding the bad clocking introduced by your router and any bad switches after the router, I suspect that has to be at least part of the reason. Of course, as this direct connection brings about even greater resolution and transparency to your system, I suspect the impact of removing bad upstream clocks or introducing reparative downstream clocks should become all the more apparent. Once I find the time, I will borrow other DACs from friends and see what kind of difference I hear but I would be surprised if I hear no difference at all.

 

With the superior clocking in place on your switch, go back to a switched instead of direct connection.

 

 

I have already done this. Using my Trend Net switch in the "direct path" as my reference, I then placed this switch just after my router and then plugged both my Mac Mini and my sMS-200 into this switch. While it did result in some improvement compared against plugging both the Mac Mini and sMS-200 straight into the router, it was quite small and definitely only a fraction of what I got with the switch in the direct path. Based on this small amount of SQ improvement, I would not find the switch upgrade to be worthwhile.