USB audio transmission isn’t bit true

[beerandmusic]

10 minutes ago, diecaster said:

You mean why did I switch from direct connect USB (computer to DAC) to a server/endpoint setup using USB at the DAC?

 

There were several reasons. One was that I wanted to stop using my office computer or my laptop to play music. I wanted a dedicated server for Roon so whatever I was doing on my computers did not affect music playback. Another was that I wanted the best sound quality possible and I knew that my noisy desktop and laptop systems talking to the DAC directly over USB was about the worst way to go in that regard. Some kind of special purpose endpoint was the way to go there. Finally, I wanted multiple "zones" to play music with all of them accessing the same music. The best way to do that was to have a Roon Core server with multiple "endpoints".  

 

Besides the last point of multiple zones, couldn't a dedicated pc connected directly to a dac do that?

I am trying to determine all the reasons why an enet solution would be superior to a pc directly connected to a dac and why.

[diecaster]

16 minutes ago, beerandmusic said:

 

Besides the last point of multiple zones, couldn't a dedicated pc connected directly to a dac do that?

I am trying to determine all the reasons why an enet solution would be superior to a pc directly connected to a dac and why.

 

Wow. I am not going through all of that. If you have not gleaned that information from this forum since you have been here....well...I don't know what to say.

[beerandmusic]

1 hour ago, diecaster said:

The premise in the title of this thread is just plain wrong.

 

People keep misunderstanding what my premise is.  The premise is merely that which Rankin stated....that USB transmission (e.g. isosynchronous) isn't bit true.  Nothing more, nothing less.  I never suggested that someone can't create a stable USB solution. Anyway, i have updated the subject to reflect what Rankin stated.

[beerandmusic]

2 minutes ago, diecaster said:

 

Wow. I am not going through all of that. If you have not gleaned that information from this forum since you have been here....well...I don't know what to say.

 

It's not for me...i learned that 8 years ago.  Anyway, i think we are on the same page as opposed to those that reject enet in their solution.

[diecaster]

8 minutes ago, beerandmusic said:

 

People keep misunderstanding what my premise is.  The premise is merely that which Rankin stated....that USB transmission (e.g. isosynchronous) isn't bit true.  Nothing more, nothing less.  I never suggested that someone can't create a stable USB solution. Anyway, i have updated the subject to reflect what Rankin stated.

 

The new thread title has a MUCH different meaning than the old title.

 

Just because USB 2.0 Audio does not guarantee data delivery is perfect does not mean that incomplete data is routinely received. It means that if some data gets messed up, it will not be resent. In fact, the ONLY reason one would even consider using a protocol that did not retransmit bad packets is if you didn't think bad packets were going to be a serious issue. Getting the bits accurately to the DAC is NOT the problem.

[beerandmusic]

8 minutes ago, diecaster said:

In fact, the ONLY reason one would even consider using a protocol that did not retransmit bad packets is if you didn't think bad packets were going to be a serious issue.

 

 

Another reason not to re-transmit bad packets is to play real time.

[diecaster]

14 minutes ago, beerandmusic said:

 

Another reason not to re-transmit bad packets is to play real time.

 

Let's assume that "real time" is an issue here (which it is not). If data arriving incorrectly was a common problem, you would hear it. You would for sure use a system that guaranteed data delivery.

 

 

[beerandmusic]

22 minutes ago, diecaster said:

 

Let's assume that "real time" is an issue here (which it is not). If data arriving incorrectly was a common problem, you would hear it. You would for sure use a system that guaranteed data delivery.

 

 

I am just saying that is likely one of many reasons that protocol was chosen rather than "because it is not a serious problem".

 

https://www.edn.com/design/consumer/4376143/Fundamentals-of-USB-Audio

and

https://www.edn.com/design/consumer/4419643/Select-your-USB-audio-MCU-with-care--Scary-stories-from-the-test-bench

 

[davide256]

1 hour ago, beerandmusic said:

I am just saying that is likely one of many reasons that protocol was chosen rather than "because it is not a serious problem".

 

https://www.edn.com/design/consumer/4376143/Fundamentals-of-USB-Audio

and

https://www.edn.com/design/consumer/4419643/Select-your-USB-audio-MCU-with-care--Scary-stories-from-the-test-bench

 

Given the improvement AL makes and that a device like ISO Regen becomes much less useful with AL, I don't believe that the significant "gremlins" are in USB...

the big problems are occurring with SW operations between read off disc and hand off to USB out. Beginning to wonder if the devices and interventions

liked before for USB enhancement were really "tuning/equalization" interventions for common OS/player USB error characteristics.

[asdf1000]

8 minutes ago, davide256 said:

Given the improvement AL makes and that a device like ISO Regen becomes much less useful with AL, I don't believe that the significant "gremlins" are in USB...

 

Not sure you'll be able to take Larry's (of LarryNUC fame) ISO REGEN + LPS-1.2 away from him though (cleaning up the output of his NUC+AL..)..

[beerandmusic]

11 minutes ago, davide256 said:

Given the improvement AL makes and that a device like ISO Regen becomes much less useful with AL, I don't believe that the significant "gremlins" are in USB...

 

Agreed...but I don't really think it is AL specific though....the fact that it is dedicated, low power, stripped down, and optimized are key.  Same can be accomplished with Windows, but it is nice that AL has created a bootable stripped down OS that can run on a dedication box to achieve a fast, easy and inexpensive solution.

[mansr]

6 minutes ago, davide256 said:

common OS/player USB error characteristics

USB typically has no errors. Assuming a perfectly realistic bit error rate of 1e-12, you get less than one bad packet per day of continuous playback.

[the_bat]

Coming late to this, and probably going to regret it.

 

My understanding has always been that when something can be described as "not bit perfect" it means that whatever it is routinely alters the bit stream in a way that may alter the perceived sound, not that there are very, very occasional errors resulting in a small amount of lost data.  This loss may or may not be audible depending on whatever is going on at the time but is completely different to a continual effect.

 

To quote a southern gentleman of my acquaintance "you done treed the wrong racoon".

[esldude]

5 hours ago, beerandmusic said:

 

People keep misunderstanding what my premise is.  The premise is merely that which Rankin stated....that USB transmission (e.g. isosynchronous) isn't bit true.  Nothing more, nothing less.  I never suggested that someone can't create a stable USB solution. Anyway, i have updated the subject to reflect what Rankin stated.

USB can have errors.  Almost never does. Why you think this is important is quite the mystery. And no one is rejecting enet audio. I wish equipment for it were more common.

 

But there is no reason to call enet audio a solution to USB audio. USB audio needs no solution as it works fine and isn't broken.

[Ralf11]

Why he think this is important is no mystery at all.  He read it on the internet.

 

And, like most people (likely at the 6 sigma level) he lacks the technical background to distinguish low res information from high res.  How does he know that you guys are right and the Rankine cycle BS engine is wrong?

 

Very few people can do that.

[AudioDoctor]

From now on I am blaming everything on USB errors...

 

Earthquake?  Thanks USB...

 

DOW drops?  Thanks USB...

 

Car breaks down? Thanks USB...

 

etc...

[Ralf11]

some guy inserting a steam punk thermodynamic joke into  a USB thread?

 

Thanks USB...

[DuckToller]

Anyone else has got the feeling the OP is closer to Rain Man than to Gordon Rankin?
Not meant as personal as it sounds, but it may help to understand, why he shows his typical behavior routine (and argumentation) so often and his immunity to all the reason he got confronted with.
This ain't funny, imho this may be some condition, you can't cure with logical arguments and technical expertise.
BaM just gets calm, if HE will find the answer HE is looking for, which, after all, excludes almost everyone apart a few chosen ones, from giving him an answer he may accept.
It's more tragic than funny, But it leads to a lot of my respect to most of you, who have tried nicely to convince him for good. Lots of good answers and description for most of us. Thank you ! Get well soon, BaM!
Tom

[sandyk]

30 minutes ago, DuckToller said:

Get well soon, BaM!
Tom

 

Most members are well aware that he has a medically diagnosed problem and processes information a little differently to most of us.

Nevertheless, he often makes some very valid points and causes people to think.

[sandyk]

7 hours ago, esldude said:

USB audio needs no solution as it works fine and isn't broken.

 Really ? Thousands of members will dispute that.

 The only thing coming into question here is whether or not this is due to Data  errors.

It isn't normally !

 Even Diecaster appears to have conceded that USB needs additional work to improve it's performance for Audio, as there is no such thing as a perfect DAC, not even your Benchmark or any USB DAC that you currently own .

I notice that members like yourself are now leaving alone Diecaster's thread which originally appeared to be formulated to attack the numerous reports in Rajiv's VERY long thread, now that several from both the Objective and Subjective sides have reached consensus about the audible effects of RF/EMI and ground loops (even capacitive coupling to earth) on the output of a USB stream to a typical well designed DAC.

 

 I do however agree that the word MASSIVE in that thread title would have better been replaced by a less dramatic sounding word to describe the improvements.  Longer term listening should have revealed very worthwhile or obvious improvements, although initially they may seem to have been dramatic/massive. 

[kumakuma]

14 minutes ago, sandyk said:

 Really ? Thousands of members will dispute that.

 

Millions of members disagree with you. 

[wgscott]

10 minutes ago, kumakuma said:

 

Millions of members disagree with you. 

 

Billions of members agree to disagree.

[sandyk]

12 minutes ago, wgscott said:

 

Billions of members agree to disagree.

 

 Especially those that use Class D amplifiers that are incapable of highlighting the obvious differences  due to the horrendous amount of RF/EMI that they inject back into the A.C. mains sewer  and ALSO radiate from their inductors to obliterate reception of nearby A.M. radios ?

[Ralf11]

3 minutes ago, sandyk said:

 

1. Class D amplifiers are incapable of highlighting the obvious differences  due to the horrendous amount of RF/EMI that they inject back into the A.C. mains and

 

2. ALSO radiate from their inductors to obliterate reception of nearby A.M. radios ? 

 

got data??

[kumakuma]

3 minutes ago, sandyk said:

 

 Especially those that use Class D amplifiers that are incapable of highlighting the obvious differences  due to the horrendous amount of RF/EMI that they inject back into the A.C. mains and ALSO radiate from their inductors to obliterate reception of nearby A.M. radios ?

 

GUTB agrees with you.