[alphaman]

Audio Science Review AES Paper Presentation on Audio DACs

I'm sure y'all've been waitin' on this ... the Man hizself has pub'd a PAPER in AES.

https://www.aes.org/e-lib/browse.cfm?elib=22278

 

[alphaman]

Note what Majidimehr, specifically mentions in the video: In the AES paper, brand names/models are not noted. (AES standard for bias???). HOWEVER , in the video and asr site [of course], Majidimehr, as an added BONUS, does note the "good" and "bad" dacs ... my manuf and model.
Oooooooooooohhhhhhhhhhhhh...... I bet Mr M. luuuuuuuuuuvs attention as he Microsoft money and can entertain us all in such a comprehensive, layered manner

 

[bigshot]

I'm guessing it doesn't address audibility with any hard testing, it just presents numbers on a page with commentary describing smaller ones being "good" and bigger ones being "bad".

 

[gregorio]

I'm sure y'all've been waitin' on this ... the Man hizself has pub'd a PAPER in AES.

Not “been waiting on this”, although I would be interested in reading it. Unfortunately I no longer have a subscription to the JAES, so I can’t. However, I’m presuming it’s effectively just a formally presented overview and set of conclusions based on the cumulative measurements/observations/conclusions he’s already posted on his website. The video you posted indicates this.

From the video, I can already easily spot a couple of issues. One is an old bugbear, Amir’s method of determining audibility is not entirely scientifically invalid but it is inapplicable (to consumer listening), this affects his categorisation of DACs. The second issue is his inclusion (and conclusions) of professional DACs. Unfortunately, Amir has little knowledge of “professional applications” and therefore his measurements of professional DACs are commonly incorrect/flawed because he doesn’t know how to use them, EG. He uses inappropriate settings, setups or comparative metrics. Furthermore, he doesn’t actually test the DACs most widely used professionally, he’s tested mostly prosumer DACs used by amateurs/serious hobbyists and those used in home/project/basement studios rather than those used by professional/commercial music and sound studios. For both these reasons, Amir’s conclusions regarding Professional DACs and where he places them as a group relative to Consumer, AV and “Custom” DACs are therefore invalid. However, these two criticisms to do not apply to his measurements and conclusions of the various categories of consumer DACs, bar the occasional measurement mistake (that he often/usually corrects).

Note what Majidimehr, specifically mentions in the video: In the AES paper, brand names/models are not noted. (AES standard for bias???).

Yes, that is entirely standard, not just for the AES but for pretty much all scientific publication platforms. There are several reasons for this, which includes but is not limited to potential bias. For example, it also avoids certain potential political, marketing and financial issues but probably the most important reason is that it avoids unjust invalidation. For instance: “Here are the results of a range of typically available DACs” (as of the publication date) vs “Here are the results of specific DACs” (named). The former allows generalised conclusions while the latter doesn’t and as soon as one or more of those specific, named DACs is unavailable, the paper is largely or at least partially invalid/useless, which somewhat defeats the purpose of a scientific publication repository.

HOWEVER , in the video and asr site [of course], Majidimehr, as an added BONUS, does note the "good" and "bad" dacs ... my manuf and model.

Of course, ASR is not a scientific publication repository, it’s a comparative review site designed for consumers of consumer audio equipment based on the scientific principles of objective measurements. Obviously it would be useless to consumers if it never stated what those consumer products actually were (“manuf and model”). So, it’s NOT an “added BONUS”, it’s pretty much the whole point of the site! I’m not sure how you can’t know this? (Although I can have a good guess!)

G

 

[alphaman]

So, it’s NOT an “added BONUS”, it’s pretty much the whole point of the site! I’m not sure how you can’t know this? (Although I can have a good guess!)

How TH do you (or anyone) know "pretty much the whole point of the site [ASR] ? I don't think even Amir knows. And, certainly, the "point" [= purpose ??] changes over time.
For example, as more an more folks send Majidimehr their gear for testing, a commitment develops into honoring those requests.
Also about that ASR site/forum ... the members and the moderators have changed the "feel" of the place. So much an echo chamber and filter bubble now. And forum moderators get locked into responsibility -- power trippin' and enjoyin'' playin' security guard at the Men' Room --urinal duty -- similar story at many "geary" forums.
All that said, I enjoy and RESPECT Majidimehr's very subtle approach to trolling the high-$ manufs. And now he's got an ASR paper to hang on his trophy wall. Along with ASR's very high Internet traffic ranking [**see SimilarWeb]]. I'm sure he's got the heads of some high-enders doubling down on their Percocet. Long live Purdue Pharma

**
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[alphaman]

Just to add ... and Majidimehr's remarks on this are spot on ... that DAC measurements -- their collection; presentation -- need to be standardized. Err. Constitutionalized. Audio magazine (RIP!!) actually began much of this from the beginning of the CD era. Stereophile/John Atkinson further refined the standards and procedures. And now, like him or not, Majidimehr has refined the process further with quite a database of devices.
Surprised Mansilla hasn't added to the pot. I mean he's got quite the setup right there in the Motor City lab ... AP analyzer and all.

 

[Voxata]

Note what Majidimehr, specifically mentions in the video: In the AES paper, brand names/models are not noted. (AES standard for bias???). HOWEVER , in the video and asr site [of course], Majidimehr, as an added BONUS, does note the "good" and "bad" dacs ... my manuf and model.
Oooooooooooohhhhhhhhhhhhh...... I bet Mr M. luuuuuuuuuuvs attention as he Microsoft money and can entertain us all in such a comprehensive, layered manner

w...what? You are a bit eccentric about all of this. The whole "higher numberer is betterer" approach has risks of its own. Pleasing distortion can absolutely enhance the listening experience. The science of such is not dissected unfortunately and when the focus or squarely placed upon SINAD... I have some great concern.

**Holy crap I just took a look at the paper, he basically states all amps and dacs are of no benefit or have acceptable performance unless they measure SOTA**

It's like saying that you should only consume the vitamins and suppliments you need. You'd survive well? Sure. But it'd be bland as hell.

 

[bigshot]

It means once you’ve consumed the vitamins you need, any further vitamins are unnecessary. A DAC with a little better specs than another means nothing if they’re both audibly transparent. Aside from NOS DACs, I think you’d be hard pressed to find one that isn’t transparent. DACs don’t have euphonic distortion, nor should they.

 

[alphaman]

**Holy crap I just took a look at the paper, he basically states all amps and dacs are of no benefit or have acceptable performance unless they measure SOTA**

Haven't seen the paper (full version) . What EXACTLY are you referring to?
" acceptable performance" could ONLY be in reference to MEASURED performance. Even John Atkinson , in the Stereophile Measurements section, commented on his ultimate recommendations/reservations based on subpar MEASURED performance. But the main (subjective) part of the review, and its editor, had the last word.

 

[Voxata]

Measurements should be used to identify problems and poor designs for sure, however one has to consider ambient noise and what the headphones can actually produce at a given volume. Measuring equipment at maximum output at levels that are not listenable isn't exactly useful. As an example at 50mv output most amps on his list measure within 10-15db of one another, so what is the point? Factor in the 60db range your headphone will be capable of and things get even more interesting. Amir concludes his testing towards the end of reviews by cranking volumes to dangerous levels to detect 'distortion' and base his claims on performance on this to reinforce his measurements. This practice makes absolutely no sense to me personally.
Yet many people will detect sonic differences between certain gear at nominal listening levels, this can be quantified as pleasing distortion or something that isn't measurable from a 1khz test tone - because a tone isn't music. Chasing the test tone is what it has become, and I'm very thankful for companies that pursue BOTH subjective and objective performance. I've owned Topping/THX gear and I've absolutely sheered my ears off with sharp treble and flat soundstages. That to me is not an acceptable performance nor is it enjoyable long term. I fatigue out. To say that this is preferable to everyone is a blanket statement and to say that any other presentation of music is inferior is quite untrue as many in this hobby have preferred otherwise.

So what I'm saying is be open, don't fulfill validation with one viewpoint and be open to experience new things that don't fall into the bucket of numbers perfected and IC driven gear. Enjoy the hobby.

 

[bigshot]

Acceptable performance for consumer products is a matter of audible fidelity, not necessarily measurements. Measurements are valuable in this context in the way they represent audible fidelity.

 

[Davesrose]

Acceptable performance for consumer products is a matter of audible fidelity, not necessarily measurements. Measurements are valuable in this context in the way they represent audible fidelity.

Well I think they can both be related. I've noticed there's a lot of audiophile debates about a component that has a DAC as being too warm or bright. I have a digital streamer with a DAC chip that audiophiles find "bright" even though if you hear the headphone stage of it, I find it sounds far from treble heavy: and that would make sense in the way that I'm listening to an analog stage. If we apply science to measure the frequency range of all these DAC chips that are either "bright" or "dark", it's not surprising that they all measure flat with the chips as far as signal: to actually hear the music, you're introducing more stages of EQ, analog stages, and transducer. These are influencing what you're hearing with your given headphone.

As for Amir, it does seem he chases ghosts with DACs when they all should acceptable with *at least* their digital outputs. But he's not an audiofool since he has rightly spotted audiophile networking items as being the ultimate of the current snake oil (apart from also the time old power cords).

 

[bigshot]

I think he overvalues his own importance and expends a lot of effort trying to bolster that image. I’m not sure what he actually believes. When I had my run in with him it was clear he knew he was cheating, but he wouldn’t admit it. It wasn’t an accident or a misconception. He was deliberately cheating. I think that might be true of a lot of people that allow their ego to be more important than just figuring things out.

Of course the first thing to do when testing something is isolating the thing you are testing. Not doing that the root of most audiophile misconceptions. But I don’t think that’s the case with him. I think he deliberately has his thumb on the scale.

 

[Davesrose]

I think he overvalues his own importance and expends a lot of effort trying to bolster that. I’m not sure what he actually believes. When I had my run in with him it was clear he knew he was cheating, but he wouldn’t admit it. It wasn’t an accident or a misconception. He was deliberately cheating.

You're talking about Amir? If so, I'd like to hear the context. So the main time I've invoked him was actually on a sponsor thread claiming their ethernet noise isolation adaptor was the crap because it was only $100 and can bring out so many highs with your streaming music. I cited one of his vids showing an audiophile router and regular consumer router: and how all measurements for noise and bandwidth were the same. One of their fans was engaging me about how there could be an objective test for this device's advantage. Then I also got one of the brand's fans saying I was breaking forum rules about suggesting blind listening tests. I do think at least in the latest snake oils of audiophile network equipment, Amir has been definitive of how networking equipment is all standardized (and how you only need to go into basics).

 

[bigshot]

He posted ABX logs for a difference that was about -70dB. He was consistently getting it right. I asked him if he was looping the fade out and gain riding it. He got huffy and acted insulted and went off on me. I asked him again politely if that was what he was doing. He refused to answer and left the forum promising to never return. A few weeks later, someone sent me a link to another forum where he was touting the same ABX logs, and some pro audio bigwigs got involved and he was forced to admit that he was doing exactly what I asked him if he was doing.

He may measure things accurately, but he is deceptive about his own ability to hear. He wants people to think his hearing is exceptional for some reason. I don’t trust his opinions about what is audible and what isn’t. Too much ego involved there.