USB to I2S conversion and reclocking quality doubt

[GUTB]

The very reason why people’s systems get cluttered with boxes is because they all make a difference. That’s why I’ve spent so much time and money in an effort to reduce my clutter building out a linear PSU PC, battery-powered PPA V3 card direct into a DSD512 DAC — the concept is I try to provide the cleanest source possible without the need for conditioners, isolators, re-clockers, etc. I haven’t even addressed the network side of things.

 

 So,  to answer the question is it a waste of money — no, this is an area in which money is well spent. A much more important question is your strategy.

[Spacehound]

2 hours ago, The Computer Audiophile said:

 Why do you care what someone spends money on?

I don't. I've got some real silly things (as have you judging from your $10,000 magic cables.)

 

So how does we  were asked about this stuff grab you ? Perhaps I should  have said he should sell it rather than he's wasted his money.

 

What's more, he  apologised and said he mistook me for somebody else.

[The Computer Audiophile]

3 minutes ago, Spacehound said:

I don't

Fantastic. I’ll hold you to it :~)

[Spacehound]

6 minutes ago, The Computer Audiophile said:

Fantastic. I’ll hold you to it :~)

I can outbid you on silly thing easy. I bought something at auction September 2017  that Ringo Starr purchased brand new in 1963.Though not because of him

 

PS: As my keboard misses letters out (I must buy  a magic cable)  I  corrected it and added some more, so you might like to read it again.

[Milt99]

Maybe my post is more of a musing than an answer but,

the thing that has struck me most when I started looking into hard drive derived or computer audiophilia is that

it seems to be the only area of home audio reproduction where a significant portion of adherents advocate for

more complexity i.e., more devices, cables etc.,  in the audio chain.

 

I have always thought that the least amount of gear between the source and the speakers was optimal.

[The Computer Audiophile]

1 hour ago, Milt99 said:

Maybe my post is more of a musing than an answer but,

the thing that has struck me most when I started looking into hard drive derived or computer audiophilia is that

it seems to be the only area of home audio reproduction where a significant portion of adherents advocate for

more complexity i.e., more devices, cables etc.,  in the audio chain.

 

I have always thought that the least amount of gear between the source and the speakers was optimal.

Hi Milt - I certainly hear you, but also suggest you look at analog playback chains. Turntables and all the accessories involved may have digital beat. I said MAY :~)

[doraymon]

16 hours ago, Spacehound said:

Perhaps I should  have said he should sell it rather than he's wasted his money.

That’s exactly my plan in case I find out that they are not worth it for me.

I need to spend more time listening but my two little devils, wife and job are absorbing 99% of my day.

B plan is waiting for the wife+kids summer retreat to Europe... I will kill my self with music!

[doraymon]

21 hours ago, GUTB said:

So,  to answer the question is it a waste of money — no, this is an area in which money is well spent. A much more important question is your strategy.

Thanks.

Yeah my strategy depends on my understanding of the topic, which at the moment is quite poor.

And I seem to have unleashed some sparkles for strong discussion. It was not my intention.

I am sure these are things that cannot be explained in a forum, but maybe I can get some direction so that I can find more material to read.

[GUTB]

1 hour ago, doraymon said:

Thanks.

Yeah my strategy depends on my understanding of the topic, which at the moment is quite poor.

And I seem to have unleashed some sparkles for strong discussion. It was not my intention.

I am sure these are things that cannot be explained in a forum, but maybe I can get some direction so that I can find more material to read.

 

CA is on the leading edge of this topic -- although General is the hangout of the non-audiophiles.

 

The information buried in large threads in the DAC and Music Server forums. That's a lot of reading. Simplified:

 

1. It's all about managing noise getting into and out of the key parts of your audio system.

2. Sources of noise: mains, switching power supplies, storage devices, motors, processors.

3. Elements of noise control: cleaning mains power, eliminating ground loops, eliminating/cleaning storage device power, eliminating switching power supplies and mechanical sources.

4. Considerations specifically for digital audio links: keeping a PC/server/streamer's noise OUT of the DAC while increasing the signal quality leading into the DAC. The DAC can create self-noise by the interface controller working trying to clean up a bad signal. Outside noise will negatively impact the DAC's input circuitry and overall performance.

 

The strategy consideration is how you go about dealing with it. Many people here go the external storage -> network isolation -> streamer -> DAC route. The key benefits are that by using a network device like a server or a NAS to store the music, you keep its noise far away from the DAC while a very low-power, low-noise streamer is responsible for feeding the DAC a high quality signal (typically also going through some form of USB or SPDIF conditioner). The network isolation technique is used to eliminate any noise being transmitted via the network.

 

Others that don't want to spend so much and/or have so many boxes to deal with just go straight from PC to DAC with significant USB conditioning in-between. This typically includes a power-blocker, high-end cable, re-clocking, etc.

 

Others, like myself, try to clean up the source as much as possible (linear power supplies, advanced clocks, boutique controllers, filters, etc and so on).

 

Some quick tips:

1. Switching power supplies are the devil, linear power supplies are good.

2. Batteries provide clean power and will also never cause ground loops. Stuff with 5V inputs can be powered by common USB power packs.

3. Clocks from better to best: VCXO, TCXO, OCXO.

4. Addressing USB noise and signal quality is essential.

5. Cheapest way to clean up the mains: run your audio gear off an un-used circuit.

 

 

[adamdea]

22 hours ago, The Computer Audiophile said:

Hi Milt - I certainly hear you, but also suggest you look at analog playback chains. Turntables and all the accessories involved may have digital beat. I said MAY :~)

Hmmm

The thing with turntables is that you can replace bits with more elaborate parts at vast expense, but is it really so much about the signal path, more mechanical structure I would have thought (part from the crazy pre amplification)?

Turntable are the real audiophile device. You can change things to your heart's content with possibly audible results. That is the whole point of the hobby. With computers you require a certain "gift" to be able to "appreciate" how tinkering with them can affect the output. Sure I guess there are people putting fancy supports under their router, but the action is a bit more fiddling with the signal path. Still everything matters, right? 

 

 

[Ralf11]

On 2/22/2018 at 6:44 AM, The Computer Audiophile said:

Why do you care what someone spends money on?

 

Consumer fraud is illegal, even if the consumers are well-heeled.

 

Additionally, society suffers when BS reigns.

[Ralf11]

doraymon - I generally agree with GUTBs post above, which summarizes several very long threads.

 

a search for the thread on Topaz isolation transformers will be informative.  I summarized it (or tried to) at one point tho that may be lost inside the belly of the beast.  I think I still have the summary and can repost if you want.

[One and a half]

On 2/21/2018 at 11:26 PM, doraymon said:

As a matter of fact I have the opposite problem, that is my upstream devices have supposedly better clocks than the D/D converter.

This is my chain: SOtM sMS-200ultra > SOtM tX-USBultra >(over USB)> Singxer KTE SU-1 DDR >(over I2S)> Holo Audio KTE Spring DAC L3

So the better clocks are upstream and the worst downstream...

Essentially the SU-1 is there to take care of the USB to I2S conversion (using its Crystek CCHD-575 clocks).

I could indeed skip the SU-1 and feed the the DAC with the USB signal out of the SOtM devices but than the DAC would in any case internally convert this to I2S, using its internal clocks which are much less precise than the 575's.

So the question is: am I wasting my money in placing $2.2k worth of "USB signal cleaning" devices before the SU-1?

I tried to do some tests by adding/removing the tX-USBultra but due to the limited space I have I can't really do a real time A/B comparison and difference was not immediately perceivable.

To add to the confusion I tried to remove the SU-1 and feed the good quality USB signal to the DAC and contrarily to the theory what I am hearing has slightly more detail, fuller bass and the sound is much less fatiguing.

 

I confess I am lost.

Sorry to be a little late in this reply.....despite best efforts, there's common mode noise on USB which unless removed will always be present.  So there's benefit of using USB cleaners on the output of any server system. Later I can find a pdf from TDK which illustrates, especially for USB Class 2.0 audio speeds at 480Mbs the effect of common mode filters.

I2S is usually transmitted over LVDS, whether it has great clocks or not another issue, since the implementation of LVDS varies greatly.

[asdf1000]

On 22/02/2018 at 12:31 PM, Spacehound said:

Do you do the same  to your wife/physician/accountant?

 

Are you wasting money? The answer's still yes.

 

Funny, I know quite a few physicians and accountants (real people, not online forums) in this hobby that believe in “magic boxes” and expensive cables.

 

They seem to be quite open into accepting perhaps not everything is fully known and improvements can be made.

 

Of course you don’t need something to be fully known for it to work practicably.

 

Turbulence is not yet a solved theoretical problem even though we have planes and rockets flying around.

 

Can you share your fully system chain? I don’t ask to judge, just interested.

 

[Ralf11]

You are thinking of an exact analytical solution to some famous equations explaining fluid flow... don't confuse that with "understanding turbulence"

 

I'm not sure what your point is regarding clinicians and accountants ??

 

They are not in scientific or engineering disciplines relating to SQ, but do usually have lots of $$ to throw down various rabbit holes, which is easier than doing some hard work to determine what really makes a difference.  You forgot to add lawyers also.

[asdf1000]

1 minute ago, Ralf11 said:

don't confuse that with "understanding turbulence"

 

Hehe noted, I made sure to mention we have planes and rockets flying around, so that it was (hopefully) clear there was no confusion.

[mansr]

1 hour ago, Ralf11 said:

They are not in scientific or engineering disciplines relating to SQ, but do usually have lots of $$ to throw down various rabbit holes, which is easier than doing some hard work to determine what really makes a difference.  You forgot to add lawyers also.

Those professions are distinctly different from science and engineering in an important way. Physicians deal with something, the human body, that is still far from fully understood. A lot of drugs are used even though nobody knows quite how or why they work. Lawyers and accountants deal exclusively with arbitrary human constructs, often ill-defined. In both cases, there is a lot of room for arguing one position or another. A lawyer need only convince twelve angry men for his version to become the actual truth. Steeped in this kind of thinking, it is natural for them to start applying it in situations where it doesn't work, such as audio engineering. Thus is born the idea that if it sounds better, the tweak works (compare, if the patient feels better, the drugs work). Explanations, let alone understanding, are not required. The notion that some things, no matter how unintuitive, are not debatable goes against everything these people know. Compound this with a tendency to equate success in one's field with general infallibility, and you have a recipe for disaster. Furthermore, the idea that one can be wrong, without even the prospect of compromise, is anathema to the mindset of these people. This makes them susceptible to the siren song of the snake oil peddlers. If they are wealthy, separating them from a piece of their wealth can be all too easy.

 

Of course, not all people with non-scientific backgrounds behave in this manner. Some put in the effort to gain at least a basic understanding of how things actually work. These efforts are generally rewarded.

[doraymon]

8 hours ago, GUTB said:

The strategy consideration is how you go about dealing with it. Many people here go the external storage -> network isolation -> streamer -> DAC route. The key benefits are that by using a network device like a server or a NAS to store the music, you keep its noise far away from the DAC while a very low-power, low-noise streamer is responsible for feeding the DAC a high quality signal (typically also going through some form of USB or SPDIF conditioner). The network isolation technique is used to eliminate any noise being transmitted via the network.

 

Others that don't want to spend so much and/or have so many boxes to deal with just go straight from PC to DAC with significant USB conditioning in-between. This typically includes a power-blocker, high-end cable, re-clocking, etc.

Thanks a lot for taking the time to write this!

Regarding the strategy, so far I went down the first route connecting my Mac Mini (Roon Server) to the home network but far away from the HiFi.

I have then placed a network isolator (AQVOX AQ-SWITCH SE), a streamer (sMS-200utra), a USB conditioner (tX-USBultra), a USB to I2S converter (SU-1) and finally my Holo Audio KTE Spring L3 DAC.

All power supplies are audio grade and all plugged in mains filters with decent quality power cords.

I am now doing some tests in the attempt to reduce the number of "boxes", namely the tX-USBultra and the SU-1.

 

From what you write I also understand that the quality of the final analogue signal being output from the DAC is not only depending on the reclocking performance of the chain (jitter)but on a number of other sources of noise.

This makes the whole thing much more complicated than I thought and the fact that the SU-1 (end of the chain) has worse colcks compared to the stremaer and conditioner (beginning of the chain) might not necessarily imply that the streamer and USB conditioners are a waste of money, as they may be cleaning other kind of noise which will not enter the SU-1 and eventually result in a cleaner signal.

 

But it's a very grey area to me, so I kind of understand some of the jokes about "magic boxes"...

[doraymon]

4 hours ago, Ralf11 said:

I think I still have the summary and can repost if you want.

Yeah thanks, that would be great!

[doraymon]

3 hours ago, One and a half said:

Later I can find a pdf from TDK which illustrates, especially for USB Class 2.0 audio speeds at 480Mbs the effect of common mode filters.

Thanks! I'm looking forward to it!

 

3 hours ago, One and a half said:

I2S is usually transmitted over LVDS, whether it has great clocks or not another issue, since the implementation of LVDS varies greatly.

...and here I'm lost again...

[doraymon]

2 hours ago, Ralf11 said:

They are not in scientific or engineering disciplines relating to SQ, but do usually have lots of $$ to throw down various rabbit holes, which is easier than doing some hard work to determine what really makes a difference.  You forgot to add lawyers also.

Even though we might agree on this, I don't think this discussion will help the understanding of any of the topics...

[doraymon]

2 hours ago, Em2016 said:

 

Hehe noted, I made sure to mention we have planes and rockets flying around, so that it was (hopefully) clear there was no confusion.

Yeah, another example is the flight dynamics of helicopters is still very much debated at theoretical level (I speak by direct experience) even though there is plenty of them flying around! 

[Ralf11]

On 2/23/2018 at 4:00 PM, mansr said:

Those professions are distinctly different from science and engineering in an important way. Physicians deal with something, the human body, that is still far from fully understood. A lot of drugs are used even though nobody knows quite how or why they work. Lawyers and accountants deal exclusively with arbitrary human constructs, often ill-defined. In both cases, there is a lot of room for arguing one position or another. A lawyer need only convince twelve angry men for his version to become the actual truth. Steeped in this kind of thinking, it is natural for them to start applying it in situations where it doesn't work, such as audio engineering. Thus is born the idea that if it sounds better, the tweak works (compare, if the patient feels better, the drugs work). Explanations, let alone understanding, are not required. The notion that some things, no matter how unintuitive, are not debatable goes against everything these people know. Compound this with a tendency to equate success in one's field with general infallibility, and you have a recipe for disaster. Furthermore, the idea that one can be wrong, without even the prospect of compromise, is anathema to the mindset of these people. This makes them susceptible to the siren song of the snake oil peddlers. If they are wealthy, separating them from a piece of their wealth can be all too easy.

 

Of course, not all people with non-scientific backgrounds behave in this manner. Some put in the effort to gain at least a basic understanding of how things actually work. These efforts are generally rewarded.

 

I generally agree...

 

except:  by definition scientists always things that are still far from fully understood.  One key to being an effective scientist is knowing what is not yet known, yet could become known with the right study using the right instruments.

 

Not all lawyers do trial work.  For some lawyers, the key is to convince one angry person (a judge) or 3 of them (appeals panel)... or xx or 9 (USSC).  Others just need to convince a single client to pay them for advice or to set things up (a will).

 

[mansr]

7 minutes ago, Ralf11 said:

except:  by definition scientists always things that are still far from fully understood.  One key to being an effective scientist is knowing what is not yet known, yet could become known with the right study using the right instruments.

Scientists strive to discover new knowledge, not to argue with it when they find it.

 

7 minutes ago, Ralf11 said:

Not all lawyers do trial work.  For some lawyers, the key is to convince one angry person (a judge) or 3 of them (appeals panel)... or xx or 9 (USSC).  Others just need to convince a single client to pay them for advice or to set things up (a will).

Not a fan of classic films?

[One and a half]

On 2/24/2018 at 11:08 AM, doraymon said:

Thanks! I'm looking forward to it!

 

...and here I'm lost again...

Here's the paper on common mode noise and filtering. The filters are very small to implement, but not featured enough on USB interfaces. We all wonder why there are differences, here's one!

 

 

TDK USB COMMON MODE NOISE eemc_practice_04.pdf