Mivera Audio DAC

[Superdad]

Well those don't look so hot. I saw the plots myself and Luiz swore they came from random samples. I'll have t get John to dig out the papers.
Of course your image above is of a 49.xxx, and ours were 25MHz.

Did you ever get any of those Pulsars or DuCoLons in to try? A bit spendy but impressive figures.
Stay away from that Accusilicon company though. I think it is a rebranding fraud.

BTW, is that your daughter in your avatar pic? She is getting big! 2 of our 3 are in college now (so that's were all the $ go...)

 

[jtwrace]

I don't know about your dac but you make cute kids.

 

[Mivera]

I don't know about your dac but you make cute kids.

Thanks. It's their mother's fault

 

[jtwrace]

Thanks. It's their mother's fault

Well, I saw her picture on your site so I'd agree.

 

[Mivera]

For anyone interested, this is how much headway was made on the subject of clock jitter in the past:

http://www.audiosciencereview.com/forum/index.php?threads/close-in-jitter.1621/

 

[jabbr]

For anyone interested, this is how much headway was made on the subject of clock jitter in the past:

http://www.audiosciencereview.com/forum/index.php?threads/close-in-jitter.1621/

Yes, close-in phase error doesn't simply raise the noise floor, rather spreads the peak.

 

[Mivera]

Yes, close-in phase error doesn't simply raise the noise floor, rather spreads the peak.

The noise floor at higher frequencies isn't near as important as the close in noise. PLL's have low noise floors but very poor close in phase noise. That's why SRC reclocker chips for SPDIF are so good at fooling the Jtest to make the jitter look good. They generate a new PLL based on a reference clock. But any quality of PLL will never come close to the actual clock pin in regards to close in phase noise.

 

[amirm]

The noise floor at higher frequencies isn't near as important as the close in noise.

Other than the fact that you have it exactly backward, that is a good statement!

From Julian Dunn, the "inventor" of J-Test you mentioned before:

The reason for above is in any introductory text on psychoacoustics. Please spend some time learning about that instead of fixating on non-audible problems.

 

[Mivera]

Other than the fact that you have it exactly backward, that is a good statement!

From Julian Dunn, the "inventor" of J-Test you mentioned before:

View attachment 8258

The reason for above is in any introductory text on psychoacoustics. Please spend some time learning about that instead of fixating on non-audible problems.

There was once a time when everyone thought the world was flat as well. Actually some still do. However as time passes, new things are discovered. 1992 was a very long time ago and we have learned much since.

 

[Thomas savage]

If you can obtain better performance, even if the benefits in terms of audibility are rendered academic , I'm all for it.

Just keep it to "these technologies bring a better performance ideal " etc rather than pinning unfounded audibility claims on them.

Most audiophiles want the best engineered solution.

 

[Mivera]

If you can obtain better performance, even if the benefits in terms of audibility are rendered academic , I'm all for it.

Just keep it to "these technologies bring a better performance ideal " etc rather than pinning unfounded audibility claims on them.

Most audiophiles want the best engineered solution.

It's been very well documented over the last couple decades that close in phase noise is highly detrimental to digital sound quality. Even in AES approved white papers as I've already shared.

https://www.by-rutgers.nl/PDFiles/clock_jitter_spec-1.pdf

Where Amir got that info from is from very outdated marketing material that comes with APx machines.

http://www.audiophilleo.com/zh_hk/docs/Dunn-AP-tn23.pdf

 

[amirm]

here Amir got that info from is from very outdated marketing material that comes with APx machines.

http://www.audiophilleo.com/zh_hk/docs/Dunn-AP-tn23.pdf

Marketing material? That is the bible of digital audio measurements.

Here is his AES paper with the same information:
Jitter: Specification and Assessment in Digital Audio Equipment

Author: Dunn, Julian
Affiliation: Prism Sound Limited,Cambridge Science Park, Cambridge, UK
AES Convention:93 (October 1992)

As I said, this is based on one of the core principals of hearing (simultaneous masking). It is not subject to word debates. You simply cannot hear close in distortions to a louder main tone. And the lower the jitter frequency, the closer the distortion noise/sidebands.

 

[Thomas savage]

It's been very well documented over the last couple decades that close in phase noise is highly detrimental to digital sound quality. Even in AES approved white papers as I've already shared.

https://www.by-rutgers.nl/PDFiles/clock_jitter_spec-1.pdf

Where Amir got that info from is from very outdated marketing material that comes with APx machines.

http://www.audiophilleo.com/zh_hk/docs/Dunn-AP-tn23.pdf

Quick scan through that, plenty about ' performance advantages ' did not see any evidence those advantages have been proven to be audible.

Like I said , I don't care but unless you have some well documented evidence to the contrary ( large scale industry accredited controlled listing experiments ) amirs stance on audibility of jitter remains valid.

I'm not intrested in hand waving or personal convictions based on what you have heard, certainly not intrested in veiled insults.

If you believe in the audibility of these performance advantages, maybe a few like superdad do too then do the work and conduct proper listening tests that can be published for peer review.

I know that's unrealistic for you on your own but maybe a consortium of sorts might band together and try and get this done?

 

[amirm]

It's been very well documented over the last couple decades that close in phase noise is highly detrimental to digital sound quality. Even in AES approved white papers as I've already shared.

https://www.by-rutgers.nl/PDFiles/clock_jitter_spec-1.pdf

Where Amir got that info from is from very outdated marketing material that comes with APx machines.

http://www.audiophilleo.com/zh_hk/docs/Dunn-AP-tn23.pdf

Funny that you say Dunn's book is marketing material where the Putzeys' paper has only one reference and is Dunn's AES paper I just quoted above!

I explained all of this before: http://audiosciencereview.com/forum/index.php?threads/close-in-jitter.1621/#post-40481

Net, net, you have no argument here. The science here is 100% solid and accepted by all.

 

[Mivera]

Marketing material? That is the bible of digital audio measurements.

Here is his AES paper with the same information:
Jitter: Specification and Assessment in Digital Audio Equipment

Author: Dunn, Julian
Affiliation: Prism Sound Limited,Cambridge Science Park, Cambridge, UK
AES Convention:93 (October 1992)

View attachment 8260


View attachment 8259

As I said, this is based on one of the core principals of hearing (simultaneous masking). It is not subject to word debates. You simply cannot hear close in distortions to a louder main tone. And the lower the jitter frequency, the closer the distortion noise/sidebands.

Maybe your bible. But to me any material that outdated means about as much to me as the bible from the church of Scientology. Most of that was written way back in the Industrial Age before the internet was even out.

 

[Mivera]

Quick scan through that, plenty about ' performance advantages ' did not see any evidence those advantages have been proven to be audible.

Like I said , I don't care but unless you have some well documented evidence to the contrary ( large scale industry accredited controlled listing experiments ) amirs stance on audibility of jitter remains valid.

I'm not intrested in hand waving or personal convictions based on what you have heard, certainly not intrested in veiled insults.

If you believe in the audibility of these performance advantages, maybe a few like superdad do too then do the work and conduct proper listening tests that can be published for peer review.

I know that's unrealistic for you on your own but maybe a consortium of sorts might band together and try and get this done?

I'm a huge fan of when both measured results, and listening tests correlate to phenomenal sound quality. To me that's how you can gauge a real winner.

 

[amirm]

Just to make sure everyone is following the discussions, both Alex's company UpTone and Mike want to sell gear based on technical specs. Problem is, t

Maybe your bible. But to me any material that outdated means about as much to me as the bible from the church of Scientology. Most of that was written way back in the Industrial Age before the internet was even out.

Nope. Again, this is direct quote from Putzeys' paper *you* linked to:

These concepts are about how we hear. How we hear changes across many generations, not years.

And again, your own expert witness quotes the same.

 

[amirm]

I'm a huge fan of when both measured results, and listening tests correlate to phenomenal sound quality. To me that's how you can gauge a real winner.

That is right. Unfortunately what you really mean above is that in sighted tests, when folks are told one box has better specs than others (never mind if it really does), folks tend to favor that gear. I can give people a wooden box with sand in it and get them to say the same thing. Nothing of importance there.

 

[Mivera]

Just to make sure everyone is following the discussions, both Alex's company UpTone and Mike want to sell gear based on technical specs. Problem is, t

Nope. Again, this is direct quote from Putzeys' paper *you* linked to:

View attachment 8261

These concepts are about how we hear. How we hear changes across many generations, not years.

And again, your own expert witness quotes the same.

Looks like you missed this very important paragraph:

 

[Mivera]

That is right. Unfortunately what you really mean above is that in sighted tests, when folks are told one box has better specs than others (never mind if it really does), folks tend to favor that gear. I can give people a wooden box with sand in it and get them to say the same thing. Nothing of importance there.

I've already explained on the other thread how Dustin Foreman (head engineer of the ESS Sabre division) and I conducted blind listening tests on identical DAC's besides the clocks. All of the industry's top engineers are on the same page as me regarding this. Well except maybe the Benchmark guy who had the finest DAC that could possibly be built 10 years ago. Anything better was beyond the threshold of audibility. But somehow keeps making his DAC's better and better with each revision. Kinda put his foot in his mouth there. However his believers still believe.