Blue or red pill?

[PeterSt]

I will make it more complex now, with the whole of the text of my previous post "in between the lines". Here goes :

 

The noise within the PC can be influenced easily by all sorts of influence on processor usage and all what contributes on the playing back of an audio file. This electrical noise implies jitter at the sender's (transceiver's) end of the PC at the outgoing stream of data. Thus, the sending chip is subject to perturbations because the current it receives is not constant in the first place because of current draw elsewhere, plus said noise causes its "threshold" firing off of the bits not to be contant in time. Here the jitter in the digital domain is born (so the signal is not getting more noisy. But jitter in the digital domain is implied. And that in itself causes perturbations inside of the DAC (the receiver doesn't work evenly fluent and its not even current draw projects on the D/A section and now causes jitter there).)

 

See the italics part ? it is the same as the text of my previous post. Mentioned "in between the lines" again, but even more crucial.

Say it is about layers of understanding.

 

Btw, the above text could be my best ever (because I understand it myself - haha).

Still apologies for the language.

 

[Audiophile Neuroscience]

30 minutes ago, PeterSt said:

43 minutes ago, Audiophile Neuroscience said:

If noise is the "effect", and it gets less....I am clearly not understanding, my apologies

 

I suppose it is quite hard to seriously digest it when I say things in between all lines (seemingly), so again :

 

There is no noise as such regarding the matter of this subject (SFS changing the sound etc.). So the signal is not getting more noisy. But jitter in the digital domain is implied. And that in itself causes perturbations inside of the DAC (the receiver doesn't work evenly fluent and its not even current draw projects on the D/A section and now causes jitter there).

 

Edit 1- Our posts crossed before Edit 2 below. I will read and digest your *last* post now.

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

Edit 2,

If I have understood, in broad terms [edit2] the electrical noise in the pc induces jitter in the pc sending chip and this is  "the effect" ie jitter in the digital domain causing perturbations downstream in the DAC. The more galvanic isolation between pc and dac the less electrical noise that gets through, the greater S/N, and thus the more revealing of these jitter induced perturbations.Like a sneaky "backdoor" in effect.

 

In an analogous fashion the iso-regen reduces downstream perturbations in the ground plane noise from upstream problems, just not jitter related, if I understood @Superdad

 

Edit 3 than you Peter

 

Edit 4...just kidding, no edit 4

[PeterSt]

15 minutes ago, Audiophile Neuroscience said:

The more galvanic isolation between pc and dac the less electrical noise that gets through, the greater S/N, and thus the more revealing of these jitter induced perturbations.

 

David, perfect.

I just came back to say the same via slightly different means : The less noise, the more distinct the jitter becomes the more easily it will imply patterns.

 

Speaking in terms of S/N incurs for great metaphors because who ever thought of applying that to a pure digital stream of data. It wasn't necessary to even think of the phenomenon, right ?

Wrong.

[PeterSt]

31 minutes ago, Audiophile Neuroscience said:

In an analogous fashion the iso-regen reduces downstream perturbations in the ground plane noise from upstream problems, just not jitter related, if I understood @Superdad

 

Minutes ago I thought of the ISO Regen again, too. But this is not so easy to incorporate in the discussion, while it is as logical as can be that it should (which is why we both thought of this, David).

 

But without going too deep into this matter, I'd say this is unrelated to the last couple of posts' subject. Or better : we can't relate it as such. The processing in such a device is too much of an unknown BUT is in very same domain as our subject as of now. Thus, whether the PC implies jitter in the digital domain or whether that device implies it (but totally different), both "do" something to this matter. But the ISO Regen would not be controllable as much (it acts as an (elastic) buffer) by upstream means.

I think it is better to talk about the old Regen's (green or amber). They imply the same processing without isolation and the processing is audible. How ? via the exact same means we talk about today.

One might just as well put random "re-generation" patterns to the digital stream, and coincidentally like one (over the other). 

[esldude]

You guys are giving jabbr a hard time over something rather trivial. 

 

What would the theoretically perfect DAC do?

 

It would deliver an accurate output based upon the sample values.  It would have zero jitter under all circumstances and have no noise.  That is the theoretical perfection.  By definition there can be no more accurate sound than that. 

 

So a DAC that isolated itself from vagaries of the digital input signal would not be effected by anything else.  Is that somehow hard to understand or controversial?  No it is not. We already know some DACs come closer to this perfection than others. 

 

So I don't know what the SFS setting is doing to alter the output of the DAC or even for certain that it is yet.  A well enough isolated DAC would only be effected by the values of the samples it reads and no setting in playback software that is bit perfect could ever effect it.  I think that is the ideal which jabbr has in mind.  If he doesn't I do. 

 

So in this context we might find DACs that sound different with different playback software activity and showing those differences would in no way show they are more resolving than a well isolated DAC because by definition the better isolated DAC is closer to theoretical perfection and would not be improved upon.  Other DACs could be different, but not better. 

 

Yes, of course I know there is no theoretical perfect DAC made physical yet. The levels that are attainable already however, put the audibility of most discussed effects so far down it really strains credibility.  

 

I do believe Mani's listening test, but that was with a 16 bit DAC which puts some constraints on things.  I know he says he hears it with much better measuring gear.  But that is yet to be tested. I don't doubt his honesty, but he is human. 

[PeterSt]

12 minutes ago, esldude said:

So a DAC that isolated itself from vagaries of the digital input signal would not be effected by anything else.  Is that somehow hard to understand or controversial?

 

Apparently. 

 

[adamdea]

8 hours ago, jabbr said:

No no no no no.

 

The electrical signals may be bit-identical without being electrically identical — nothing to do with the DAC. 

 

A perfectly isolated DAC, according to my understanding of the term “isolated”, will have the same sound regardless of electrical differences in the “bit identical” incoming bitstream — eg a regen or other isolating device, would, if the DAC were perfectly isolated, not make a difference in SQ.

I’m not sure we are disagreeing. The starting point would imho be a dac which scores a very good j test on toslink. 

If you can make that sound different between bit identical inputs you are on to something. 

 

[adamdea]

7 hours ago, manisandher said:

 

I've had DACs (and digital interfaces) here from Weiss, RME, Pacific Microsonics, Mytek, Schiit, iFi, AR-T, Esoteric and Chord. They were all, without exception, affected by similar bit-identical changes to those used in the A/B/X. All were 'well designed', from the perspective of current thinking.

 

If you believe current thinking is an open-and-shut case, go ahead. But there'll be no progress.

 

I'd reframe your question as, "What is causing all current DACs to have outputs that vary audibly according to the non-information properties of the input data?"

 

Something useful will inevitably come from this.

 

Mani.

Well that’s of course is the probandum. It would be interesting, aside from other avenues of inquiry, to see whether the results are repeatable with something like a benchmark. 

You seem confident. I suspect they are too, although for different reasons.

[adamdea]

10 hours ago, Andyman said:

 

Hmm. I like your posts jab and you know your stuff, but not sure on this. It’s sort of a circular argument which may well support the exact opposite of its own intent. Funnily enough, my first thought was not too dissimilar from that of Adam (who incidentally I think has been given a bit of an unfair ride of late in this thread)...

 

 

Not to worry: more heat than light, as usual. The things are simply playing out as one would expect. The points I was making haven’t changed. They may have something in them; they may not. We will see.

[PeterSt]

13 minutes ago, adamdea said:

The points I was making haven’t changed. They may have something in them; they may not. We will see.

 

I think your points are quite OK lately. But if I see correctly, your style changed a little. 

Thanks. 

[manisandher]

14 hours ago, psjug said:

Are any difference in the analog captures (the music ones) apparent when comparing small sections of time series plots?

 

14 hours ago, psjug said:

I know they won't match exactly.  But maybe obvious and consistent differences can be shown, especially in sections where Mani is most hearing the differences.

 

I'm not sure what a 'diff' program would find (I know you have to be careful with dud results from some of them). I suspect the signals are too complex or "chaotic" to identify any consistent differences between the two playback means, even within just a small section of time. The fact that the human ear can suggests that this is perhaps another inappropriate measurement.

 

But if anyone is interested in trying this, I'll be uploading soon the analogue captures that we took when Mans was here.

 

Mani.

[manisandher]

4 hours ago, PeterSt said:

You know, there's so much theorizing around in CA. Every body knows best.

 

Especially how they would have done things differently. But it remains a "would have" and not a "did do".

 

The world in which we live...

 

Edit: I'm not in any way directing this towards anyone contributing to this thread. I've very much enjoyed the recent pages of this thread, and feel that everyone's contribution has been interesting and valuable.

Mani.

[semente]

9 hours ago, manisandher said:

I've had DACs (and digital interfaces) here from Weiss, RME, Pacific Microsonics, Mytek, Schiit, iFi, AR-T, Esoteric and Chord. They were all, without exception, affected by similar bit-identical changes to those used in the A/B/X. All were 'well designed', from the perspective of current thinking.

 

What about the Phasure?

[Summit]

I very much agree with @fas42 that to solve problem with noise* we need to think system instead of gear or components.

 

Noise* can IMO be divided in to 3 principal groups: airborne noise, noise transmitted by the mains power and noise transmitted by cables that are carrying the data or audio signal. But there are no free lunch, meaning that no filters or isolation can be made completely perfect and with no undesirable by-effects. The negative effects can of course be much smaller than the gain of the filters or isolation, but never as good as if no noise had to be filtered out in the first place. Am also a firm believer in that a revealing and transparent DAC/AMP/speakers should be true to the source and if we has to use filters or isolations that are filtering at frequencies that are close to the digital signal, bits will not flipped but other negative SQ effects that we today don’t know much about and how to measure and quantify can be heard.    

 

All types of noise* are by-products generated by transmissions, power regulations, data and signal processing, PSUs and so on. To minimize the noise that are transmitted by cables we should strive for, that the noise that can’t be eliminated is made with, a noise profile that’s has a totally different frequency than the digital signal has (heterogeneous to the digital signal). Because if it’s not imbedded in the signal itself it can be filter it out which is more difficult if the noise* has the same frequency or characteristic as the digital signal.

 

To minimize the noise* that’s airborne or transmitted by the mains power we should try to keep all the digital data processing and its power supplies, monitors etc. separated and as far from the audio gear as possible. I.e. put all source and computer gear in another room and on different mains power line so the only connection between the source and DAC is by the digital cable. 

 

*Noise in this context are all the undesirable signals and pollutions like RFI, EMI, phase noise, leaked current, jitter etc etc.  

[semente]

8 hours ago, pkane2001 said:

SFS is processing done by XXHE software on the PC, before data is converted to SPDIF stream and output to the DAC. The bit-identical in this test refers to exactly the same samples being transmitted from the PC to the DAC with two different SFS settings.

 

What this doesn't account for is any variation in sample timing (jitter) or noise being carried with the digital signal or along other pathways. Both can potentially have an audible effect on the output of the DAC, despite exactly the same bits (samples) reaching it in the two test scenarios.

 

Can we determine which of those SFS settings results in a more accurate conversion, or does it have to be a taste-driven choice?

You seem to be pointing at jitter, other to phase...

[semente]

4 hours ago, PeterSt said:

 

I suppose it is quite hard to seriously digest it when I say things in between all lines (seemingly), so again :

 

There is no noise as such regarding the matter of this subject (SFS changing the sound etc.). So the signal is not getting more noisy. But jitter in the digital domain is implied. And that in itself causes perturbations inside of the DAC (the receiver doesn't work evenly fluent and its not even current draw projects on the D/A section and now causes jitter there).

 

See ? another one in between the lines (braces !). Sorry for my style of writing.

 

Can you measure or visualise that jitter-inducing disturbance in the force, pardon, stream?

 

Also, you seem to be implying that the disturbance cannot be dealt with at DAC level but has to be "solved" upstream, correct?

[pkane2001]

48 minutes ago, semente said:

You seem to be pointing at jitter, other to phase...

 

Whats the difference between phase noise and jitter?

[mansr]

5 minutes ago, pkane2001 said:

Whats the difference between phase noise and jitter?

None.

[mansr]

I'm surprised nobody has questioned what the meaning of the word "is" is.

[Audiophile Neuroscience]

19 minutes ago, mansr said:

I'm surprised nobody has questioned what the meaning of the word "is" is.

 

That pretty much sums it up !

[semente]

55 minutes ago, pkane2001 said:

 

Whats the difference between phase noise and jitter?

 

50 minutes ago, mansr said:

None.

 

[Summit]

1 hour ago, pkane2001 said:

 

Whats the difference between phase noise and jitter?

 

Phase noise is measurements of variations in signal timing presented in the frequency domain.

 

Jitter is measurements of the variations in the time domain. We have two different types of jitter: deterministic and random.

[Summit]

1 hour ago, mansr said:

I'm surprised nobody has questioned what the meaning of the word "is" is.

 

Why should we?

 

Present tense third-person singular of be

Dialectal present tense first-person and third-person singular of be

Dialectal present tense plural of be

[pkane2001]

24 minutes ago, Summit said:

 

Phase noise is measurements of variations in signal timing presented in the frequency domain.

 

Jitter is measurements of the variations in the time domain. We have two different types of jitter: deterministic and random.

 

Phase noise or jitter are not measurements, they are the actual variation in timing of digital samples, which can be measured in frequency domain or in time domain. Regardless of how you measure them, they represent the same physical effect.

[pkane2001]

34 minutes ago, Summit said:

 

Why should we?

 

Present tense third-person singular of be

Dialectal present tense first-person and third-person singular of be

Dialectal present tense plural of be

 

Where were you when the then president of USA needed help with this?