USB audio cracked... finally!

[seeteeyou]

It would be so much fun if Hi-Fi News were testing a group of USB cables again and include The Lush, then we could compare the eye pattern with others

 

http://mvicha.sweb.cz/test USB kabelu.pdf

http://mvicha.sweb.cz/test USB kabelu 2014.pdf

Quote

In essence, this cable offers the smooth, creamy lushness of the warmer-sounding cables and yet combines this with a spaciousness and the sparkle of the livelier sounding cables.

 

[manisandher]

5 minutes ago, seeteeyou said:

It would be so much fun if Hi-Fi News were testing a group of USB cables again and include The Lush, then we could compare the eye pattern with others

 

22 hours ago, PeterSt said:

And btw, the fact that the eye diagram changes, tells me nothing. Good enough is good enough as this is pure digital (no D/A conversion).

 

Mani.

[mmerrill99]

1 hour ago, bibo01 said:

Funny you say that. I was thinking to get a Lush just to send it to my friend (JK).

Yes that would be excellent - is the broadband radio receiver JK uses a difficult build & the technique to connect to scope? Maybe if that was detailed some others could do the same measurements.

 

My post of JKs measurements of USB cables got no interest here so maybe there isn't a desire to do these type of measurements?

[lmitche]

10 hours ago, PeterSt said:

 

So that, right ? And the USBPC is at the PC side I suppose ... 

 

Thus yes, that would "kill" the regeneration, but retain the isolation. Similar to the NOS1a/G3 where the USB isolation is at the other end (in the DAC). So on that matter, the isolation "anywhere" seems sufficient.

 

Funny ...

Peter, the Lush is definitely being fed a regenerated signal from the ISO Regen in this configuration, so the full benefits of the ISO Regen, both isolation and regeneration/reclocking are being enjoyed.

[PeterSt]

So ... This should be a great day;

After seeing those eye diagrams from the hifinews magazine and trying to interpret what could sound how, today I'll make me a test setup so I can show to myself how what looks.

 

The fun of this is - and I sort of announced this longer ago already - that I am heavily biased. I mean, I already know what (cable) setup sounds how, but I deliberately never measured it.

 

Looking at the hifinews pictures, it is easy to see how all measurements are subject to a general system behavior (like PC or USB interface). My setup will be subject to that too, but the interface(/DAC) I will set up for it, should be as general as possible. Thus, nothing like NOS1a/G3/SYZ/ABC etc. Actually just the USB interface with special measurement pins and the best "probe loading" I can (this latter in itself is not easy at all and maybe I can't even do it without disturbing the signal - we'll see).

 

To give a few ideas of what I intend to achieve today for testing :

1. The Supra USB 2.0 which s*cks to me and other NOS1a owners (but which many like a lot) and which is advertised as being to USB2 spec.

2. A generic $1 cable which always comes with the NOS1a and which was the best for a long time.

3. The Clairixa, that being the best to spec cable, if all is right (at least I know exactly what it is).

4. The Lush, that being a deliberately out of spec cable (let's see to what degree ! ha !)

a. With Intona.

b. With Phisolator (DAC Side).

x. With Regen (amber) at PC side.

y. With Regen (amber) at DAC side.

z. With double Phisolator (DAC side).

 

Ad z.

Nobody but me has experience with this because I can't make it consistently working (so far), but the sound coming from it is totally crazy. All sounds completely live from it, and you really can't determine whether it is a studio recording until the end, when the applause lacks.

 

Ad a, b, x, y, z.

I think I will do this with the Clairixa as this is supposed to be the best to spec cable and thus should show the best what happens with other devices in the chain. Of course the #3 measurement will be the base to compare with, at least in theory at this moment of writing.

 

Anyway what I intend is testing 1, 2, 3, 4  separately and next take one of those to combine with a, b, x, y, z.

This in itself should be with 2x Clairixa as this is done like that all over the globe (almost everyone with the Clairixa also has the "Short Clairixa for Intona").

 

Peter

 

 

 

[PeterSt]

I should add that it seems obvious to also test different lengths of the same cable, but I will save that for later. Thus, we will first see the general outcome of the test as announced, then try to interpret what we actually see and then compare with shorter and longer lengths of either Lush or Clairixa, but let's that make the Lush because people will be interested in that the most. Or ... now I think of it, what about a "fine to spec" cable (Clairixa) and how it behaves at longer lengths and compare that to the "bad spec" cable (Lush) for the same. Hmm.

 

Btw careful ... I see myself writing about "bad spec" but the Lush is not that at all. Because remember, it was made to "audio spec" and all what that tells is that it is not equal to USB2 spec (for sure ).

[bibo01]

30 minutes ago, PeterSt said:

So ... This should be a great day;

After seeing those eye diagrams from the hifinews magazine and trying to interpret what could sound how, today I'll make me a test setup so I can show to myself how what looks.

 

The fun of this is - and I sort of announced this longer ago already - that I am heavily biased. I mean, I already know what (cable) setup sounds how, but I deliberately never measured it.

 

Looking at the hifinews pictures, it is easy to see how all measurements are subject to a general system behavior (like PC or USB interface). My setup will be subject to that too, but the interface(/DAC) I will set up for it, should be as general as possible. Thus, nothing like NOS1a/G3/SYZ/ABC etc. Actually just the USB interface with special measurement pins and the best "probe loading" I can (this latter in itself is not easy at all and maybe I can't even do it without disturbing the signal - we'll see).

 

To give a few ideas of what I intend to achieve today for testing :

1. The Supra USB 2.0 which s*cks to me and other NOS1a owners (but which many like a lot) and which is advertised as being to USB2 spec.

2. A generic $1 cable which always comes with the NOS1a and which was the best for a long time.

3. The Clairixa, that being the best to spec cable, if all is right (at least I know exactly what it is).

4. The Lush, that being a deliberately out of spec cable (let's see to what degree ! ha !)

a. With Intona.

b. With Phisolator (DAC Side).

x. With Regen (amber) at PC side.

y. With Regen (amber) at DAC side.

z. With double Phisolator (DAC side).

 

Ad z.

Nobody but me has experience with this because I can't make it consistently working (so far), but the sound coming from it is totally crazy. All sounds completely live from it, and you really can't determine whether it is a studio recording until the end, when the applause lacks.

 

Ad a, b, x, y, z.

I think I will do this with the Clairixa as this is supposed to be the best to spec cable and thus should show the best what happens with other devices in the chain. Of course the #3 measurement will be the base to compare with, at least in theory at this moment of writing.

 

Anyway what I intend is testing 1, 2, 3, 4  separately and next take one of those to combine with a, b, x, y, z.

This in itself should be with 2x Clairixa as this is done like that all over the globe (almost everyone with the Clairixa also has the "Short Clairixa for Intona").

 

Peter

 

 

 

Hi,

Great Peter!

I understand that you are going to use all those cables and devices, but what are you actually going to measure?

[PeterSt]

Just now, bibo01 said:

what are you actually going to measure?

 

Hi - I realize that "measure" is a big word here, because I won't measure as such. Only show (eye diagram).

What I could try to measure is jitter but I am not so sure this can be done reliably. It depends on what I see for "pattern" and how the scope triggers to that.

Additionally, I don't think that jitter will really do something to better sound, would it be about lower jitter. So really, higher jitter may imply a better sound because it influences current draw in the receiver and there is no way that anyone in the world is going to reason (to me) how lower jitter will sound better, in this domain.

 

In the very end the eye pattern will also tell nothing when seen without context. But the fun is that with the context of what we know (which is merely what I myself know) about how the various situations sound we will see the "graph" which belongs to that sound (and not s stupid number which jitter is, which can be peak to peak jitter only in my (scope) case).

[Speed Racer]

This is all going off the deep end. We are dealing with digital data here. This isn't analog where the cable can act as a filter to color the analog signal. Assuming none of the bits get flipped, the ones and zeroes are all fine and don't change regardless of the USB cable used. We should be looking at ways to cause the receiver to do as little as possible to contaminate the circuits on the DAC. This would include low noise power, proper ground with no ground loops, and data signal that causes the USB receiver to be as clean as possible. Most cables, with or without an isolator of some type, get the one and zeroes right. It's the other stuff that goes along with it that is the problem.

 

Because of this, a cable that works well for one DAC USB receiver may not work well for another. For one DAC, the UpTone Audio ISO Regen/USPCB combo might work best. For another, it might be ISO Regen and this lush cable. For another, who knows? If you have no way of looking at what happens inside the DAC, all you can do is test to see which sounds better to your ear. But the idea than any one cable is the end all solution is ludicrous!

[PeterSt]

In that hifinews magazine they mention the rise time as one of the "measurements" (actually it is the only measurement). But suppose I want to do the same, does someone know what they use to get to the numbers ? Is it 90% of the maximum voltage ?

Anyway, the way they do it does not look reliable (or useful) to me, especially because it depends on the shape of "wave" while it is just *about* that shape, largely.

[PeterSt]

11 minutes ago, Speed Racer said:

But the idea than any one cable is the end all solution is ludicrous!

 

Yup. And so one would claim the same for software settings. Still a 1000 people dial in the same settings (out of countless) and hear the same.

Not that I would have guessed 10 years ago that this could happen, but is just appeared so. And because it happens like that, we can now go beyond stupidness like software settings, and continue with D/A converters, USB cables, Interlinks, anything.

 

Anyway what I read so far from Lush owners, all claims are the same and besides are consistent with what I perceive in the room over here.

 

11 minutes ago, Speed Racer said:

We should be looking at ways to cause the receiver to do as little as possible to contaminate the circuits on the DAC.

 

Yes, you are funny.

 

24 minutes ago, PeterSt said:

So really, higher jitter may imply a better sound because it influences current draw in the receiver and there is no way that anyone in the world is going to reason (to me) how lower jitter will sound better, in this domain

 

But I was first. Plus I am mean.

So maybe it slipped your attention that it is all about hat. This is also how I said that we can think as the cable being a filter, but which is not the truth. It can imply a filter though. Elsewhere.

 

Maybe you are among those who are dead-certain that software settings (buffer settings) do not influence sound. Then stop reading. But otherwise :

How do you think that works then ?

Answer : the very same.

[manisandher]

21 minutes ago, Speed Racer said:

If you have no way of looking at what happens inside the DAC, all you can do is test to see which sounds better to your ear.

 

We have:

• “First seconds already ... WoW!”
• “WOW indeed...”
• “I am using Lush now for 1 day. Very first impression, I am missing something. But within some tracks I started to appreciate the sound. Really smooth and warmer but with same details AND better bass again.”
• “Perhaps it is because I am still in the honeymoon period (my The Lush arrived this morning) but this cable is "the business".  Harmonics anyone?  The albums that I have listened to so far have been very enjoyable. Yes the sound is more lush, or perhaps even warmer, than the Clarixia.  It kind of reminds me of why people choose triodes and 4 or 5 way acoustic systems...that depth of presentation with a harmonic richness to soothe the soul.”
• "Lush has arrived here and all I have to say is: WOW !!!! It is like all digital "stuff" has been removed from my system and replaced with analogue.”
• "... The Lush is probably the best money I've ever spent in audio.”
• “The Lush gives my system a 'natural' and 'analogue' sound. Instruments and voices are both full-bodied and crystal clear at the same time. The whole sound resonates beautifully, with a natural decay.”
• “I then changed to the Lush cable(not really burned in yet) and I must say that this is the one. It just gives you the analogue feel together with details. The violins are silky and yet you can still hear them conveying to you the feelings. No excessive full bodied sound. And listen to the gentle decay of the sound at decrescendos and sound slowly dying away. The microdynamics are all there and most important with feeling. And when the solo piano comes in the percussive notes is both authoritative and musical. Very difficult to achieve. And the musical sound and transparency and details are always there and never gives you fatigue. I must say that this is definitely my preferred sound.”
• "The Lush now is more of a night-and-day sort of thing to me. It is really stunning how transformative this cable is to my whole system. Music sounds like real now, something I was looking for a very long time when tuning around my DIY power supplies and all that stuff. Now I'm so much closer to the sound I'm dreaming of..."
• "Conclusion - the Lush just sounds nicer. Hard to express, but I think Mani said more musical and that's as good a phrase as I can muster. More twang in the strings. More air in the vocals. Slightly less digital." 
• "I have to say it's a keeper.  I want to call it the "classical cable" and while it adds value to all musical genres, I have truly enjoyed listening to classical music for the first time in a long while with this cable. The level of harmonic detail, timber and emotion it delivers is better then anything I have ever heard. Peter is right, it's not an a/b thing, its best experienced by listening to an entire album."
• "What is really remarkable about the sound of the Lush is that it is both smoother sounding and, at the same time, everything, instruments and voices, are more solid sounding. Everything has more "presence", thus everything sounds more natural... Incredible achievement."

Many different DACs and setups.

 

Mani

[marce]

19 hours ago, Jud said:

 

Sorry, I was thinking "threshold-crossing" but saying "zero crossing," so that understandably created confusion.  So back to the original question: if the slope in this figure is altered, the threshold-crossing point is altered, yes?  Or is this not the slope you are talking about altering?

 

DC offset, yes.  Same with noise on ground (if that is in fact separate from what you are referring to as DC offset - maybe not).

The slope is the same for each period so the switching points is the same.

[PeterSt]

Just now, marce said:

The slope is the same for each period so the switching points is the same.

 

Yes. But expect the sound to be different !

The electrical behavior will be different. Notice the complex of happenings and together they form the net behavior.

[Superdad]

1 hour ago, PeterSt said:

Hi - I realize that "measure" is a big word here, because I won't measure as such. Only show (eye diagram).

What I could try to measure is jitter but I am not so sure this can be done reliably. It depends on what I see for "pattern" and how the scope triggers to that.

 

Hi Peter:

I assume you have the proper USB test fixture boards for performing your eye-pattern tests?

 

1 hour ago, PeterSt said:

Additionally, I don't think that jitter will really do something to better sound, would it be about lower jitter. So really, higher jitter may imply a better sound because it influences current draw in the receiver and there is no way that anyone in the world is going to reason (to me) how lower jitter will sound better, in this domain.

 

Too bad you have just the original USB REGEN and not the vastly improved ISO REGEN on hand.  I am not sure why you postulate that low phase-noise does not matter in the USB application.  The is ZERO doubt that our use of the Crystek 575 in the ISO REGEN--along with dozen other things we do, including USB3.1 hub chip and 5 world-class LT3042 regulators--is an important SQ factor.

 

In development we made boards that were 100% identical except for the clocks.  One had standard low-jitter Crystek 3391 as used in thousands of USB REGENs, the other had the 575 (which by the comes out in current production with far batter 10Hz-offset figures than Crystek's own web page shows: -108dB to -112dB for a $10 clock is extraordinary).  From the first notes comparing the two boards it took all of 15 seconds to know that the ultra-low-phase noise clock was the clear winner.

 

It may not make any sense that the phase-noise "fingerprint" of a USB data clock somehow influences the DAC's USB PHY and processor (just as SI and impedance match does), but there need not be any doubt about it when listening.  Peter, you yourself mentioned that you went to a Crystek 575 for your own USB input board, so really this is no surprise to you.

 

Best,

--Alex C.

[mmerrill99]

3 minutes ago, marce said:

The slope is the same for each period so the switching points is the same.

Eh, sorry? Isn't that what jitter is? A change in the transition point caused for whatever reason, the slew rate has changed (slope is not the same); change of shape in the waveform; etc.?

[PeterSt]

7 minutes ago, mmerrill99 said:

Eh, sorry? Isn't that what jitter is?

 

I don't think it was that what was implied (by Jud) - or at least it wasn't stated. So, change that level (as in DC offset) does not change a thing for jitter (unless the trigger point starts to be at the top of the wave because then it is under influence of more noise).

[mmerrill99]

@PeterSt - if you are doing eye pattern measurements, it might be useful to try to capture the USB  waveforms that are very far off the norm. A normal eye pattern plot doesn't show these very well

 

A measurement of eye patterns that John Westlake did showed these "LF runt pulses" as he called them & showed them by using a scope which does color grading of the plots - so where there are no waveforms, the color is black, where there are a heavy concentration of waveforms the color is white - it's an easy way to see the distribution pattern of the USB pulses.

[marce]

6 minutes ago, mmerrill99 said:

Eh, sorry? Isn't that what jitter is? A change in the transition point caused for whatever reason, the slew rate has changed (slope is not the same); change of shape in the waveform; etc.?

We are talking periodic signal rise time, not anything else, jitter is a variance of the periodic signals switching. The signal rise time will depend on the driver IC the line impedance and any terminations in the line, it will be the same for each wave period, it can change a small amount, this will show up on the eye diagram.I am trying to dispel is the often followed belief that fast rise times are better than slow... NO the correct rise time is always best.

[PeterSt]

10 minutes ago, Superdad said:

I am not sure why you postulate that low phase-noise does not matter in the USB application.

 

Hi Alex,

 

And I am not sure where you get that from !

 

11 minutes ago, Superdad said:

Peter, you yourself mentioned that you went to a Crystek 575 for your own USB input board, so really this is no surprise to you

 

All correct. That is why I don't know how you think that I think differently.

But I know ... I know ...

 

You seem to think that what's happening for signal in the cable is the same as what's needed to suck in that signal (which is what the oscillator does, in the end). I'm not saying that both are unrelated, but it's different "domains".

[PeterSt]

3 minutes ago, mmerrill99 said:

A measurement of eye patterns that John Westlake did showed these "LF runt pulses" as he called them & showed them by using a scope which does color grading of the plots

 

Oh yes, sure !

But I must first get myself acquainted by this and I don't have the time to spend ages on it. What I mean is, to do such "measurements" one also needs to know about the data. And although I have protocol analyzers as well, I don't know a thing about USB data. Or how to generate the required data for this. Understand ?

[mmerrill99]

26 minutes ago, marce said:

I am trying to dispel is the often followed belief that fast rise times are better than slow... NO the correct rise time is always best.

I agree that the risetime needs to be no faster & no slower than needed.

A lot depends on the USB receiver & it's slew rate limitation - USB 3 receivers being better by design, in this regard

[PeterSt]

19 minutes ago, Superdad said:

Too bad you have just the original USB REGEN and not the vastly improved ISO REGEN on hand.

 

And Alex, I have been on the verge of stipulating that we could exchange some gear so I could use the ISO-Regen for this.  But I didn't because I'd have to wait for it while I have time for this today and probably not on any other day. Well, as you know, I promised you something ... 2 years ago ? And now this day has come.

OK, my mind is set to it finally.

 

One other thing : I am not on to subjective judgments other than what many know already, similar to what a few now know about the sound of the Lush cable. So my idea it to show why a cable etc. sounds like it does and then by means of the eye diagram.

So put yourself back one year. What was the advice : put the Regen close to the DAC. That is fine and we will see why that is.

I hope.

[Jud]

29 minutes ago, marce said:

jitter is a variance of the periodic signals switching

 

Sometimes when you repeat something enough different ways, it eventually penetrates.  Thanks, marce.

[firedog]

On 7/15/2017 at 3:44 PM, JoeWhip said:

Simply due to Mani's history talking up Phasure and talking down other DACs. This whole things reads a lot more like pushing Phasure than simple enthusiasm. If Phasure wants to send me a cable, I'll listen and report. Otherwise, not interested.

Not especially directed at JoeWhip, but just a comment:

 

People really need to get off Mani's case. He likes the Phasure and says so. He doesn't say other DACs suck, just that his favorite is the Phasure.  He doesn't in general talk down other DACs. He doesn't like the Schiit Yggy. His taste.

If you look around the audio based internet, there are lots of people who think the Yggy is great. There's also a not insignificant minority that thinks it really doesn't sound right.  So Mani isn't alone. 

 

I don't see why that is a problem. Other people like Lampizator, PSAudio, Mytek, etc.  Can't people express a preference either positively or negatively without getting attacked?

When someone else doesn't love a product you think is the best thing you've ever heard, they aren't attacking you personally. They're saying that for their ears and taste, they didn't like "X".

 

Grownups can handle that without going "forum crazy" on another poster or criticising him at every opportunity.