CLOCKS, what should we look for in next generation

[davide256]

1 minute ago, beerandmusic said:

have you messed with sotm ultra?  or you are not a believer also?

Haven't heard it yet, I'm sure its great but I  think the microRendu is fine in my system, leaps and bounds above the Aries mini for low level signal resolution. More concerned about DAC USB connectivity , so have an Eitr ordered. If that doesn't satisfy, I see a Schitt Yggdrasil in my future, auditioned it at CAF and it was wonderful.  Keeping my fingers crossed as I'd prefer to spend the money instead  on Audeze LCD-3's.

 

Net of all that wandering is that I am philosophically un-inclined to buy an "ultra" anything unless the DAC is first of that quality.

[PeterSt]

3 minutes ago, davide256 said:

If that doesn't satisfy, I see a Schitt Yggdrasil in my future

 

I heard from a reliable source that Yggs are also good for playing DAT tapes. 

[beerandmusic]

17 minutes ago, davide256 said:

Haven't heard it yet, I'm sure its great but I  think the microRendu is fine in my system, leaps and bounds above the Aries mini for low level signal resolution. More concerned about DAC USB connectivity , so have an Eitr ordered. If that doesn't satisfy, I see a Schitt Yggdrasil in my future, auditioned it at CAF and it was wonderful.  Keeping my fingers crossed as I'd prefer to spend the money instead  on Audeze LCD-3's.

 

Net of all that wandering is that I am philosophically un-inclined to buy an "ultra" anything unless the DAC is first of that quality.

ok, so microrendu...at least you got the same concept as sotm, so likely on par....also agree with a dac of equal, which is why i want to buy one box from same manufacturer with rendu similar and dac eliminating need for usb interface...i am guessing the main thing that differentiates microrendu and sotm ultra is the clock.

[PeterSt]

8 minutes ago, beerandmusic said:

.i am guessing the main thing that differentiates microrendu and sotm ultra is the clock.

 

Which clock, where ?

(I ask, because it seems that you missed something else)

[d_elm]

2 minutes ago, PeterSt said:

 

Which clock, where ?

(I ask, because it seems that you missed something else)

The sCLK-EX board, 4 clocks with a master, in the sMS-200ultra.

[davide256]

deleted

[jabbr]

7 hours ago, beerandmusic said:

A search will show the sclkex is a OCXO, and John Swenson substantiates the OCXO here as well.  A google search of OCXO and DSD will produce very few hits (comparatively speaking for google) but the likes of AUrender W20 and Antelope and a couple other welll recieved gear appear.  I have to believe there is something good scratching the surface....Also, i have always been stating that I believe (go back 4 years in these threads), that to me native DSD over network sounds best regardless of dac...and now this area is really getting some traction with the sonore and sotm.

 

The take home message should be that it is the phase error plot which is the important spec, not whether there is an “OCXO”. If you would like 1 single number to look at: take the dB/Hz @ 1Hz offset ... many phase error plots don’t give you 0.1Hz.

 

Turns out that this number correlates with 1/f noise. That’s why good power supplies are important because if the power supply has high 1/f noise, then the clock will suffer. The power supply can’t just be “low noise” but has to have low 1/f noise.

 

In any case if I were to rip out and replace the clock that @PeterSt put in his NOS1a DAC and replaced it with the SoTm sclk-ex then I would be an idiot. I have no idea if the clock is an OXCO.

[fas42]

6 hours ago, beerandmusic said:

my logic suggests to me that "possibly audible jitter" really is loss in detail.

 

Something along those lines - poor digital playback I've heard over the years suffered from: loss of low level detail; dead, lifeless, boring tonal quality; or aggressive, screaming in your face, razor sound. Often, combinations of these, err, qualities. One thing I have never, ever done was to fiddle in the clock area - got very close to it at one point, even bought me a super duper, lowest phase noise crystal - but never installed it. Mainly because, sorting out noise and interference issues via other means did the job well enough, and I was too lazy to pursue it further ... .

[semente]

19 hours ago, beerandmusic said:

I am not an audio engineer, nor do i pretend to be...i am merely trying to educate myself as little as possible

 

 

I'm sorry for the slight bluntness but that seems to be the problem. You should educate yourself more, not as little as possible.

That is why most of your assumptions are off target.

[semente]

16 hours ago, beerandmusic said:

I really, REALLY, do not have any desire to understand any of it....I just want someone to say "look for these features" in your next purchase. 

 

People are telling you that's not the way it works. But you're trying very hard not to listen. @Charles Hansen summed it up quite nicely the other day...

[semente]

10 hours ago, beerandmusic said:

 

you don't need a "pc"... you can use  a quiet audio designed processor in a network player. that supports it's own storage or from nas.  I want to move away from trying to resolve for pc usb shortcomings and need for usb toys or specialized cables.

I would guess than an sotm ultra to a mytek brooklyn playing native dsd could compete, and if the likes of a lumin d1 could make their same box with ocxo in a nextgen single unit box, it could compete as well.

I am sure exasound could put their playpointe in the same box as their e32 and could likewise compete.  I believe we are just scratching the surface with new advances in  noise supression and clocking.

 

 

 

 

Beer, you may not know it but @PeterSt is as far as I know the only manufacturer selling the whole package: software, dedicated computer and DAC. And he knows what he is talking about.

[mansr]

11 minutes ago, semente said:

And he knows what he is talking about.

Too bad nobody else knows what he's talking about.

[semente]

7 hours ago, beerandmusic said:

I don't know...i would think the whole purpose of clocking is to get the digital signal to the converter accurately....don't know why we would need more than one clock?  But i am not an audio engineer....

 

 

You are asking interesting questions but not listening to the replies.

[semente]

8 minutes ago, mansr said:

Too bad nobody else knows what he's talking about.

 

I think that he did OK in this thread (if you are referring to PeterSt)

[esldude]

8 hours ago, davide256 said:

I lived it... apparently you weren't born, or were outside the audiophile community at the time. Or perhaps worked for one of the businesses selling Denon turntables?

Negative on all counts.  

 

I was alive too, and remember no industry wide campaign to discredit belt drive.  For that matter if you ever had the pleasure of hearing a Micro Seiki (the model with up to three tonearms) you can hear that not all direct drive was inferior to belt.  Plenty of marketing by of course big companies selling direct drive.  Not the same thing as you imply.   

[fas42]

47 minutes ago, mansr said:

Too bad nobody else knows what he's talking about.

 

Not quite, nobody else ...

[beerandmusic]

1 hour ago, semente said:

 

Beer, you may not know it but @PeterSt is as far as I know the only manufacturer selling the whole package: software, dedicated computer and DAC. And he knows what he is talking about.

 

i knew peter makes dac and software, but didn't know he also sells computers....and don't forget cables...

 

I know he is very knowledgeable, I was just saying I don't think there is a need to have a pc or a usb interface....I know he already knows that, i only stated that someone can use a network, processor direct to dac without pc or usb because that is where my interest is....

[PeterSt]

5 hours ago, beerandmusic said:

i only stated that someone can use a network, processor direct to dac without pc or usb because that is where my interest is....

 

By now it should more or less occur to you that you have not many contenders for that idea. This, why it is so obviously logical that I should be the only one against it, you dozens being in favor. But somehow and with not too many spoken reasons it is the other way around - you are alone.

 

So what seems to happen is that you ask the questions (again, mostly good ones and you even incur for nice debates or better thinking-over (on our or at least my part)), but all decisions have already been made by yourself. So you seem to be full of stipulation, kind of want confirmation but next don't like to listen much.

Am I right ?

(no clue yet what to do with the answer - haha)

[PeterSt]

By now I have dozens of designs, two of them incorporating full blown processing in-DAC which would be what you seem to head for, beer. I think I even have the PCB's for one of these designs. Point is :

 

Whatever the configuration exactly is or can be made (al is always modular), I can reason out in advance that it will be a noisy mess.

The disadvantage in me is that I already deal with the electrically noisy environment in a PC at miles of distance, and with controlling that noise, controlling the DAC's behavior. And yes, the (USB) interface is sure part of that, hence it is a major source of "noise" / audible nastiness. And now you ask me to avoid the USB interface and put the whole source of further electrical noise right next to the fragile D/A process.

So yes, it is an approach, but I don't see it happening for the better, and this is how I stick to designs (up to almost always PCB production). DSD the same things. I can't count the DSD designs any more, even with discrete ladder DACs (to name something wild). But there is no reason. In my view of course and most certainly not by law.

 

Maybe the moral is that even when working on these matters year after year, I myself can not decide, or "know" that the result will be worse than the solution at hand. Maybe you can do it by means of a couple of more threads and questions ?

 

PS: Talking about DSD : I was so (un)smart that I had the idea that DSD requires a (for jitter) way better clock assembly than PCM, thinking that a 1 bit system would be 24 times more sensitive to jitter than a 24 bit (R2R) system. Although this will be less than half-true, I made such a thing and tested it on the regular DAC we have.

It did not work because it was ultimately sensitive to the environment (vibration) and I couldn't think of a way to damp it. The bass was completely crazy and it sort of required a kidney belt to survive it. This is no kidding and it was unlistenable for that reason alone. But it indicates what is possible, eventually.

So @jabbr, same NOS1a (not G3 back at the time) and a sound which drops your jaw literally, only because of a different clock assembly (sub femto and the -160 I mentioned earlier on with a best supply to my knowledge).

So see Beer, you have your questions mostly right. The answers are not at all easy to give (and fail within your budget, although I should stop saying that).

[beerandmusic]

22 minutes ago, PeterSt said:

By now I have dozens of designs, two of them incorporating full blown processing in-DAC which would be what you seem to head for, beer. I think I even have the PCB's for one of these designs. Point is :

 

Whatever the configuration exactly is or can be made (al is always modular), I can reason out in advance that it will be a noisy mess.

The disadvantage in me is that I already deal with the electrically noisy environment in a PC at miles of distance, and with controlling that noise, controlling the DAC's behavior. And yes, the (USB) interface is sure part of that, hence it is a major source of "noise" / audible nastiness. And now you ask me to avoid the USB interface and put the whole source of further electrical noise right next to the fragile D/A process.

So yes, it is an approach, but I don't see it happening for the better, and this is how I stick to designs (up to almost always PCB production). DSD the same things. I can't count the DSD designs any more, even with discrete ladder DACs (to name something wild). But there is no reason. In my view of course and most certainly not by law.

 

Maybe the moral is that even when working on these matters year after year, I myself can not decide, or "know" that the result will be worse than the solution at hand. Maybe you can do it by means of a couple of more threads and questions ?

 

PS: Talking about DSD : I was so (un)smart that I had the idea that DSD requires a (for jitter) way better clock assembly than PCM, thinking that a 1 bit system would be 24 times more sensitive to jitter than a 24 bit (R2R) system. Although this will be less than half-true, I made such a thing and tested it on the regular DAC we have.

It did not work because it was ultimately sensitive to the environment (vibration) and I couldn't think of a way to damp it. The bass was completely crazy and it sort of required a kidney belt to survive it. This is no kidding and it was unlistenable for that reason alone. But it indicates what is possible, eventually.

So @jabbr, same NOS1a (not G3 back at the time) and a sound which drops your jaw literally, only because of a different clock assembly (sub femto and the -160 I mentioned earlier on with a best supply to my knowledge).

So see Beer, you have your questions mostly right. The answers are not at all easy to give (and fail within your budget, although I should stop saying that).

 

Thank you for taking time to respond.  I know you are very smart, and knowledgeable, but It is my belief that sometimes it may take more than one engineer to create an optimal system design.  The Lumin D1 already exists that pretty much meets all of my expectations...I am just thinking of possibly a v2 that incorporates newly gained knowledge of advancement in clocks.  I also am convinced that there will be MANY MANY MANY more network players on the horizon that will ultimately be the defacto standard replacing pc based usb dacs....jmo of course, we will have to wait and see.  I predicted DSD would be supported by AVRs about 4 years ago on this site, and was laughed off this board.  Of course there is the possibility I am wrong, but I don't think so, or i wouldn't publicly make such a statement.

[Superdad]

15 hours ago, beerandmusic said:

Is it possible that if we didnt have a usb interface, e.g. network to dac in one box, that we could just have one clock?

 

Other that the exception I will mention, one clock will never be the case.  

Every processing chip (and even some chips that we don't think of as processors) needs a clock source.  So for the interfaces it does not matter if it is an Ethernet switch or PHY, a USB hub or PHY, the processors or FPGA associated with them, they all need a clock source.  As does any general purpose processor, be it a ARM or Intel type, or graphics or DSP.  

Such clocks will most always be at whole number frequencies, 12MHz, 13MHz, 24MHz, 25MHz being the most common.

 

Audio rate clocks as part of a DAC will never match those: they will typically (with exceptions for ASRC or very high sample rate conversions) be multiples of 22.5792MHz and and 24.576MHz.  

And there really is not much good reason to source together the various chip clocks and the audio bit clocks since most designs are already doing their best to keep these circuits isolated from one another.

 

There is one method that can be effective if done right: And it is a category which John well and will likely post about as he has time.  Those are clock synthesizers, the most modern of which can even go a ways to attenuate jitter.  Generally these chips get pair with a really good, low phase-noise reference clock (XO or OCXO) of any selected frequency.

BTW, the SOtM clock boards use a clock synthesizer chip (and a reference of unknown caliber) to generate the multiple selectable frequencies you see offered on their web site.

 

--------------------------

 

Separately, I will state that we think what is needed to advance is a wholly different interface between computer and DAC/DDC.  One that truly is immune to all upstream vagaries and cables.  But one that does not require anything in the form of processor, OS, or driver s/w in the DAC--and which can run over long lengths of wire with no degradation.

It may take another year for this to come out--and we do not hold any illusions about instant acceptance/adoption, but this is one of the things that John and I have been working towards for a long time.  I will not say anything more about it, so don't ask.  Suffice it to say that the status quo, with regards to computer>DAC interfaces, may not stay the same forever. 

 

[beerandmusic]

2 minutes ago, Superdad said:

 

Other that the exception I will mention, one clock will never be the case.  

Every processing chip (and even some chips that we don't think of as processors) needs a clock source.  So for the interfaces it does not matter if it is an Ethernet switch or PHY, a USB hub or PHY, the processors or FPGA associated with them, they all need a clock source.  As does any general purpose processor, be it a ARM or Intel type, or graphics or DSP.  

Such clocks will most always be at whole number frequencies, 12MHz, 13MHz, 24MHz, 25MHz being the most common.

 

Audio rate clocks as part of a DAC will never match those: they will typically (with exceptions for ASRC or very high sample rate conversions) be multiples of 22.5792MHz and and 24.576MHz.  

And there really is not much good reason to source together the various chip clocks and the audio bit clocks since most designs are already doing their best to keep these circuits isolated from one another.

 

There is one method that can be effective if done right: And it is a category which John well and will likely post about as he has time.  Those are clock synthesizers, the most modern of which can even go a ways to attenuate jitter.  Generally these chips get pair with a really good, low phase-noise reference clock (XO or OCXO) of any selected frequency.

BTW, the SOtM clock boards use a clock synthesizer chip (and a reference of unknown caliber) to generate the multiple selectable frequencies you see offered on their web site.

 

--------------------------

 

Separately, I will state that we think what is needed to advance is a wholly different interface between computer and DAC/DDC.  One that truly is immune to all upstream vagaries and cables.  But one that does not require anything in the form of processor, OS, or driver s/w in the DAC--and which can run over long lengths of wire with no degradation.

It may take another year for this to come out--and we do not hold any illusions about instant acceptance/adoption, but this is one of the things that John and I have been working towards for a long time.  I will not say anything more about it, so don't ask.  Suffice it to say that the status quo, with regards to computer>DAC interfaces, may not stay the same forever. 

 

Thanks, i was already corrected and acknowledge the need for more than one clock...it was just a thought hoping to inspire another (besides an unneeded pc to usb interface) cost savings, and jitter elimination circuitry that could potentially exist in a single manufacturer network player dac in one box.  My only effort is to inspire manufacturers to what I perceive as an optimal solution, but realizing of course, that I am not an audio engineer.  With the common pc->usb->DAC interface, engineers continue to try and resolve for the usb interface, while in my mind that interface should simply be eliminated....interesting that you suggest here that NO processor would be needed in this design you are working on, that has me flabbergasted.  I think that I would prefer that a processor is needed for many reasons....if for no other reason a "web interface" (wink).

[beerandmusic]

23 minutes ago, Superdad said:

 

 

Separately, I will state that we think what is needed to advance is a wholly different interface between computer and DAC/DDC.  One that truly is immune to all upstream vagaries and cables.  But one that does not require anything in the form of processor, OS, or driver s/w in the DAC--and which can run over long lengths of wire with no degradation.

It may take another year for this to come out--and we do not hold any illusions about instant acceptance/adoption, but this is one of the things that John and I have been working towards for a long time.  I will not say anything more about it, so don't ask.  Suffice it to say that the status quo, with regards to computer>DAC interfaces, may not stay the same forever. 

 

re-reading, ok, you are suggesting ethernet based fiber approach, and still need for processor, but as a separate device...those already exist, but would be over the budget I am in.  Concepts similar to LUMIN D1 will prevail for my budget.

 

You had me concerned about no processor, but you are just suggesting no processor internal to the fiber network dac.

 

I believe that your proposed design will reign superior to what i have in mind, but not at my price point...PS- good luck, I think it is in the right direction for that audience....but i think that will be a more "niche" market, but possibly more profitable for small manufacturer.

 

[Superdad]

11 minutes ago, beerandmusic said:

re-reading, ok, you are suggesting ethernet based fiber approach, and still need for processor, but as a separate device...those already exist, but would be over the budget I am in. 

 

That s NOT AT ALL what we are working on.  Don't even bother trying to guess.

[beerandmusic]

7 minutes ago, Superdad said:

 

That s NOT AT ALL what we are working on.  Don't even bother trying to guess.

haha....i tried. (wink)