Testing audiophile claims and myths - Page 89

Quote:

Originally Posted by Chris J 

LOL!

 

I meant buying it blind folded out of a choice of several!   No testing involved!

Read the specs, the features, over and out, no endless agonizing over the best "sounding DAC".

Even the mighty Absolute Sound said that all DACs sound almost identical in one of their digital issues.

Must of had a moment of weakness in the editorial staff........

 

I'm thinking of an Arcam rDAC because it is Apple compatible, and has several different types of digital inputs!

I'm thinking either DacMagic+ (Dacmagic 100 for cheaper?) or Musical Fidelity M1 DAC A because the previous gens measured very well.
And both have plenty of features.

Quote:

Originally Posted by khaos974 

I'm thinking either DacMagic+ (Dacmagic 100 for cheaper?) or Musical Fidelity M1 DAC A because the previous gens measured very well.
And both have plenty of features.

 

 

Take this with grain of salt, but if you look on the DACMagic Plus thread there seems to be a lot of controversy over the sound of the DacMagic Plus.

Maybe that just means it's too popular!

Quote:

Originally Posted by Chris J 

Quote:

Originally Posted by khaos974 

I'm thinking either DacMagic+ (Dacmagic 100 for cheaper?) or Musical Fidelity M1 DAC A because the previous gens measured very well.
And both have plenty of features.

Take this with grain of salt, but if you look on the DACMagic Plus thread there seems to be a lot of controversy over the sound of the DacMagic Plus.

Maybe that just means it's too popular!

There also was plenty of controversy about the sound of the original DacMagic, it still performed very well on the test bench .

Well I could also recommend the Anedio D2, there's no (or very little) controversy on the Anedio D1 thread, and the measured performance is textbook excellent, we jump a whole price category though.

Thank you, PRM, this is highly related to my interest and fantastic summary.

I do find it curious that so few head-fi orientated DACs and amps come with published THD figures. If they did, then surely there would be a easy way to bypass a lot of "it sounds great / it doesn't sound that great" back-and-forth threads, just compare and see which has the most uniformly low distortion across the frequency spectrum. Of course there are other considerations to take into account, but its a good starting point.

Is there anybody out there taking the same measurements of multiple dacs / amps for comparison purposes? It would be a handy complement to skylab's portable amp rankings, there may be a correlation between THD and his ranking.

Given how low THD figures are these days, I don't know that we'd find much correlation to audibility. But it would be interesting to run the comparison. 

Quote:

Originally Posted by saggett 

Is there anybody out there taking the same measurements of multiple dacs / amps for comparison purposes?

http://www.milleraudioresearch.com/avtech/index.html

You need to register, but it's free.

Quote:

Originally Posted by D. Lundberg 

 

http://www.milleraudioresearch.com/avtech/index.html

 

You need to register, but it's free.

Thank you so much for that link. The results are fascinating. Often more fascinating is the comparison between subjective reviews and the objective performance. The pass/fail criteria seem considerably more generous for black disk spinners ((i.e allowing a speed error of 1% as a pass !) but that is for another time) but they test digital components (and cables for heaven’s sake !) whose performance is so bad they label the test sheets as Fail (the 1^st gen Sony CDP101 passes but the £10,995 McIntosh MCD1100 fails) but HiFi mag reviewers sometimes consider them the best thing since sliced bread. This is truest for shiny and/or very expensive components. What can we make of this? Are the reviewers simultaneously capable of detecting miniscule differences in forwardness and airiness yet incapable of hearing grotesque distortion or huge amounts of jitter? Could it be we as humans are just not very good judges of sound quality? Could it be that even very ordinary specs are simply overkill?

This is very interesting.  I personally think jitter is a very misleading and misunderstood metric, especially when treated as some isolated numeric value.  Many reviewers seem to agree that certain DACs show pretty much no change between different transports, while other DACs they claim can be moderately improved by using a separate SPDIF transport.  test files available online tend to show that magnitude of jitter alone does not seem to have much of an influence over audible sound quality.  Personally I think that Jitter is a metric which is only useful for the actual engineers designing the products as it really has to be understood in terms of the overall effect it might have on the performance of a piece of equipment in terms of distortion etc (again I think distortion is another fairly mute metric).  Unless you are someone that properly understands what jitter is and the possible consequences on the performance of a piece of equipment you may be designing looking at jitter and distortion figure will not really yield much useful insight.  The numbers are just not that useful by themselves unless you know what to do with them.

Quote:

Originally Posted by nick_charles 

Thank you so much for that link. The results are fascinating. Often more fascinating is the comparison between subjective reviews and the objective performance. The pass/fail criteria seem considerably more generous for black disk spinners ((i.e allowing a speed error of 1% as a pass !) but that is for another time) but they test digital components (and cables for heaven’s sake !) whose performance is so bad they label the test sheets as Fail (the 1^st gen Sony CDP101 passes but the £10,995 McIntosh MCD1100 fails) but HiFi mag reviewers sometimes consider them the best thing since sliced bread. This is truest for shiny and/or very expensive components. What can we make of this? Are the reviewers simultaneously capable of detecting miniscule differences in forwardness and airiness yet incapable of hearing grotesque distortion or huge amounts of jitter? Could it be we as humans are just not very good judges of sound quality? Could it be that even very ordinary specs are simply overkill?

Hi, I think that a part of the answer is the recordings people are listening too. When everything is processed it will be hard to agree upon what it actually sounds like when there is no original source (like a real life acoustic performance). So the quality becomes entirely subjective.

Quote:

Originally Posted by drez 

This is very interesting.  I personally think jitter is a very misleading and misunderstood metric, especially when treated as some isolated numeric value.  Many reviewers seem to agree that certain DACs show pretty much no change between different transports, while other DACs they claim can be moderately improved by using a separate SPDIF transport.  test files available online tend to show that magnitude of jitter alone does not seem to have much of an influence over audible sound quality.  Personally I think that Jitter is a metric which is only useful for the actual engineers designing the products as it really has to be understood in terms of the overall effect it might have on the performance of a piece of equipment in terms of distortion etc (again I think distortion is another fairly mute metric).  Unless you are someone that properly understands what jitter is and the possible consequences on the performance of a piece of equipment you may be designing looking at jitter and distortion figure will not really yield much useful insight.  The numbers are just not that useful by themselves unless you know what to do with them.

Jitter is the audiophile moral panic for the 2000s - there have been a few studies which have mapped jitter magnitude to levels of random noise and correlated distortion sidebands. Dunn's papers quantify the "effective resolution" hit of jitter and there is a robust cottage indusrty in jitter-kilers but oddly little empirical evidence as to the deleterious audible consequences of moderate levals of jitter beyond dog and pony shows and anecdotes. The few published empirical papers on jitter audibility suggest jitter outside of utterly egregious amounts just is not an issue but if a Sterophile compnent hits 1ns peak to peak jitter its tut tut ! while a turntable cen get away with 1.3% speed variation - sigh

Quote:

Originally Posted by GrosseFuge 

When everything is processed it will be hard to agree upon what it actually sounds like when there is no original source (like a real life acoustic performance). So the quality becomes entirely subjective.

Yes and no. You can control for the effect individual components have - even without knowing the "original" source. E.g. CD + DAC + Amp + Speakers - if you only swa out the DAC, you can make a direct comparison to how it affects the system, without having the original. What you cannot say is that any of them are more true to source. So it is subjective in that sense - the whole experience is subjective, but you can make objective measurements and tests of components within that frame of reference. 

Quote:

Originally Posted by liamstrain 

 

Yes and no. You can control for the effect individual components have - even without knowing the "original" source. E.g. CD + DAC + Amp + Speakers - if you only swa out the DAC, you can make a direct comparison to how it affects the system, without having the original. What you cannot say is that any of them are more true to source. So it is subjective in that sense - the whole experience is subjective, but you can make objective measurements and tests of components within that frame of reference. 

I agree but since the recording is not true to real life it's entirely subjective how to interpretate it. The recording is a big problem here. If the recording is so processed and harsh, it might not be so strange that many people might prefer a weak performing CD player who rolls of the highs and adds some nice "warm" distortion here and there. Actually, I think the instruments alone are already a problem (like drums, and electric guitars). Since the listeners have never heard these in real life, or only processed by the live installation how could they possibly pick out the best measured equipment consistently when it's entirely subjective on what the sound actually is. Apologies for my poor writing!

I'm not even talking about preference. Most of these discussions are whether a difference can even be detected. Any difference at all can be described, regardless of the nature of the original source. 

I am curious, if small amounts of jitter make no audible difference then what is the most likely explanation for audible differences between different digital interfaces (Coaxial, Optical, USB)? I have personally observed that an Audio-GD NFB-10SE sounds somewhat drier and less airy over the USB interface compared to the Coaxial, though unfortunately I didn't do a blind comparison at the time.