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In DAC, Anything audible but unable to be measured(so far)?

solderdude

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But what would it have to do with DACs ?

The only approach would be to demonstrate differences between a 'magic high-end DAC' and an ordinary one that are evaluated as one being able to and the other one not.

And why would one want to compare this using devices that introduce (comparatively) shitloads of distortions of all kinds and record analyze that when one also can compare the analog waveforms directly (Paul's software).
 

onion

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Part of the question posed in the title is about what can be heard but not measured so far. I'm offering a tentative answer to that. And binaural microphones are simply measuring devices - they do not introduce distortions.

I would not be surprised if in ten years from now there exists a standardised process and measure for spatial resolution for consumer devices like DACs. One of the researchers in this field expressed to me frustration that there were so many talented engineers and scientists working on jitter-free DACs with low distortion that the field is now over-engineered. It is a solved problem where the improvements in measurements are now happening at levels inaudible to humans. Whereas spatial resolution remains an unsolved problem with fewer talented scientists working on it.
 

solderdude

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Part of the question posed in the title is about what can be heard but not measured so far. I'm offering a tentative answer to that. And binaural microphones are simply measuring devices - they do not introduce distortions.

What can not be measured in spatial cues from a DAC.. we can measure in ps. we can measure in nV, we can measure in GHz.
Where would the spatial clues be in if not in that area.
We can compare (null) analog outputs of electronic devices. There should be measurable differences that show superiority.


Binaural nicrophones are anything BUT simple measuring devices. They have huge linear distortions (well over 10dB) that are also direction dependent.
As they pick up sound waves these sound waves need to be generated. This process involves electromechanical transducers that have lots of distortions of various kinds/types. Then we have the distortions created by reflections.
A microphone picks up the combined sound pressure of all sounds.
How can that be more revealing and accurate than a direct waveform comparison without alll those non-linearities added ?
 

SIY

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Whereas spatial resolution remains an unsolved problem with fewer talented scientists working on it.

Why would a talented scientist work on an "issue" which has never been demonstrated to exist?
 

onion

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They are supposed to measure what is heard at the left and right ear. The difference at any given moment should relate to spatial cues as to where sounds are localised in the sound field. For this type of measurement, distortions emanating from the speakers/ DAC would presumably cancel out between left and right ear.

However, I am not wedded to the idea that it must be a binaural mic. Any kind of precision audio measuring device that measures at the entrance to left and right ear simultaneously should do the job equally well or better.

Room reflections affect how audio is heard by the listener so should be picked up. For a standardised test of a system's ability to reproduce spatial resolution with high fidelity, an anechoic chamber or other standardised environment could be used.

For those that believe spatial resolution isn't a thing, is everyone who writes about soundstage differences between different DACs hallucinating?
 

SIY

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For those that believe spatial resolution isn't a thing, is everyone who writes about soundstage differences between different DACs hallucinating?

With the exception of the odd pathological DAC, I'd use the word "mistaken." That's why you need proper listening data, done level matched and double blind, not just internet anecdotes. Without that, no serious researcher is going to bother to chase after something that from a signals point of view makes no sense whatever. Get actual listening data and people will chase it.
 

RichB

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Aside from signal to noise and distortion measured here the filters implored can have a audible effect (IME).

Benchmark uses Linear Phase filter (not selectable). This from John Siau:

I would add one more: The phase response needs to be linear. You can have a flat frequency response without having a linear phase response and the non-linear phase response will change the way transients sound. A non-linear phase response will have no impact on a continuous set of tones, but it will change the apparent frequency response of transients.

https://www.audiosciencereview.com/...f-benchmark-ahb2-amp.7628/page-17#post-180486

Our ears are relatively insensitive to phase response on steady-state combinations of a fundamental and a series of harmonics. However, we are quite sensitive to phase response on transients. If the high-frequencies arrive first, they are accentuated. If the high frequencies arrive late, the impression will be that they are rolled off. An impulse, such as drum rim shot produces a broad spectrum of frequencies. A perfect impulse produces all frequencies simultaneously. The sound of this impulse will change when the phase response is changed. Many D/A converters use filters with a non-linear phase response. These filters change the way an impulse sounds. The changes will be most noticeable in the percussive content of the music. It has become popular to manipulate the sound with non-linear filters. These filters are an effect and some people enjoy having these effects applied to their music upon playback. The down side is that these effects are cumulative. Each pass through a non-linear phase filter will add more audible effects. In contrast, many A/D and D/A processes can be cascaded when the converters have a linear phase response. We have demonstrated this with some in-house listening tests that we conducted with cascaded converters.

The differences can be measured if you run the right tests. The differences will not show up in the frequency response (amplitude response).

Beware of time-domain response plots because they often look at only one phase relationship to the sample clock. An "improved" filter response may not look so good at other phase relationships to the sample clock. Filters that allow aliasing will pull transients toward the nearest sample clock edge (distorting the transient).

The Oppo UPD-205 defaults to Minimum Phase Fast but has selectable filters that measure differently and do sound a bit different to me.
They can be easily switched using the Oppo app to perform quick comparisons.

- Rich
 

onion

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With the exception of the odd pathological DAC, I'd use the word "mistaken." That's why you need proper listening data, done level matched and double blind, not just internet anecdotes. Without that, no serious researcher is going to bother to chase after something that from a signals point of view makes no sense whatever. Get actual listening data and people will chase it.

I don't work in the field. But an example of how to get the data would be:

In a standardised room with standardised speakers, first record the measurements at the ears of a live performance using multiple sound emitters (does not have to be music).
Then record the same measurements using the playback of that live performance using the DAC with speakers.

One could build up a picture of how closely different DACs approximate the live performance measurements. If this correlates with listener subjective experience of spatial resolution (done double-blind as you say), then voila! We have a means of measuring spatial resolution for different DACs (and indeed speakers and amplifiers).
 

SIY

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All you have to do is measure the electrical output of the DAC, unless you believe that the downstream components magically change when they see the brand of DAC being used.

What you propose is the equivalent of trying to measure the width of a hair using a wooden yardstick.
 

restorer-john

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Why would a talented scientist work on an "issue" which has never been demonstrated to exist?

Judging by the sheer number of media reported long term 'scientific studies' that appear to re-iterate the bleedin' obvious, I've come to the conclusion many scientists desire lucrative commission work, and will happily take on anything, if it pays the bills. :)
 

SIY

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I've come to the conclusion many scientists desire lucrative commission work, and will happily take on anything, if it pays the bills. :)

If onion wants to fund his rather... novel proposal, I'll be happy to take his money.
 

restorer-john

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If onion wants to fund his rather... novel proposal, I'll be happy to take his money.

Could be rather expensive for Onion. Don't longitudinal studies involving an exclusively contracted scientist and many participants over an extended period require a considerable investment in specialized new equipment (power cubes etc)?

At least a purpose built laboratory and a helpful assistant as a bare minimum:

1563228587062.png
 

Duckeenie

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Design as in visual design, not electric/electronic. Brand has nothing to do with it really. If you brand of DAC is audible different than any other (exception, filters) then you should get another one that's made correctly. Brand is more a about customer relations, service and support after the thing is sold. But that's just my opinion.

Jokes always work much better if one doesn't analyse them. :)
 

Blumlein 88

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One approach could be to measure sound at the listener's ears with binaural microphone - for both the live performance and the stereo reproduction of that live performance played though the loudspeakers. This would demonstrate measurable differences between the two forms of sound reproduction that could be correlated with their subjective perception of spatial resolution.

https://audiophilestyle.com/ca/revi...ker-comparison-with-binaural-recordings-r768/

This isn't exactly what you mean, but maybe along the lines. Recording two different speaker systems binaurally. BTW, mitchco posts here if you wanted to ask questions.

Of course how do you measure the live performance except with microphones?

I can provide recordings of music over speakers in my room plus the original recording. I can save you the trouble and tell you our ears/brain don't hear the same as microphones in the same spots. Binaural gets closer, but still isn't same. Stereo is a limitation in all this, not the DACs.
 

amirm

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If there are two DAC and both have perfect measurement, say 0% THD and also good score in everything else that's been used to test DACs.

Is it possible that there are ANY kind of difference in how they sound like?
Sure. The #1 thing is that their output levels are different so when you switch one for the other, you immediately notice a difference in fidelity even though it may just be volume.
 

Tks

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What an odd posting on Massdrop..

First off, made by someone who you would think did his research, but makes a massive blunder about Amir's credentials when they're all bare for anyone to take a look at.

Second, the link he gives to SABF.. is possibly the worst place on the planet in terms of audioclowns. Even me with a rudimentary understanding of most of this stuff, I've managed to find these retards slipping about. They remind me of some pseudo SJW's (as opposed to actual social justice warriors that do work in fields like human/civil rights). They want to call bs on some measurements, when if that were the case, the company in question would be going after Amir instantly for slandering potentially. So just like idiots today who feel offended on behalf of Jews(when for example a vegan says what the animal agriculture is engaged in today is a literal Holocaust) because their ancestors suffered the Holocaust, these people want to suffer something for Schiit, when Schiit themselves see no error.

Also, this place is riddled with mentally deranged people who think good performance metrics can be faked. The same sort of people who think the THX 789 and Atom are pointless and sterile devices.

So just going by natural human bias (in the same way you would think of people who you might observe to eat shit daily, safe to say you wouldn't want to have dinner with them), I tend to have a bias against listening to what people like the "purr1n" guy on SABF says. These people simply failed far too many litmus tests of rationality and sanity to ever be taken seriously (even if indeed they ever made good points in the future, there comes a time when you stop giving people chances especially if they don't rescind every single thing they've said in the past).

Third, Amir, like any other person has his quirks. He sometimes does stuff that doesn't make sense to me (sometimes because I have no idea of the technical nature because it's something that requires an actual education in the electrical field for example) and sometimes he just does, or says things that don't actually make sense due to typo's or not understanding the gist of something or the contexts around it.

The point being.. who cares? He could be a secret racist for all that matters to me, it has zero impact in the educational and revealing nature of the work he engages. I could think he's dumb for thinking a certain way or whatever, but what does that have anything to do with the content he's provided here (and the reviews + measurements of gear)?

See folks, this is my main problem with audiophool nonsense. And posts like the one on Massdrop (even though the second link leads to a dead-end link).. These people will hark on a person for supposedly starting a cult. A cult of what..? Objectivists? How is this bad exactly?

I see this same idiotic non-critical thinking nonsense in religious vs atheist circles. You tell religious folks you're just not convinced God exists, and you have science the ever progressing handed-down method of attempts at better understanding our world. NOPE, they say because you don't know the Big Bang's actual nature, while they do (that being God, which doesn't actually teach us anything, it only further compounds the issue by presenting us with a bigger problem of understanding a more complex thing like God).

So here's the kicker, so lets say we say fuck-off to doing things scientifically as we cultists here prefer. What's the alternative? Belief in non-evidenced based claims? Are these people LITERALLY retarded? How many times must it be demonstrated to these people that their way of doing things doesn't actually make sense from a critical thinking perspective? Then you'll get the apologetic reasoning "oh but we say just go by your ear, we're not telling you what to believe, just listen to your emotions" and wishy washy nonsense like that.. Except if you give them an inch, they take a mile by then having this sort of mentality leak into scientific deliberations, and before you know it, they'll be making claims like that one stupid fuck (I forget his name, but said he can hear down to -300 db or some such other nonsense, Amir would know his name if he reads this).

And no matter how many times you tell them: "it's okay, you believe whatever you want, that's fine, just don't bleed your nonsense into fields you have no place in, nor do you believe in the basic concepts that science has established, and even the products you use are now based on the total opposite behavior that you now engage in". That's when they get pissed, and start these sorts of threads about the "ASR cult" or whatever such idiotic declaratory statements.

So, in conclusion, even if Amir has some problems, or inconsistencies that random people on the internet might perceive (like ever other normal person on the planet who has their own quirks), why would that even matter? It's like saying "Because Newton actually (and he did) had more writings about religion, that we should disregard all of his scientific contributions". Absolutely ridiculous...

And also, the fact that they attempt to attack the person, and not the science itself (because the half-sensible among them know they get shot down constantly when they battle in that arena), is telling of desperate grasps at straws.

The ONLY portion of the linked Massdrop thread that makes sense was about "getting a second or third opinion" on things. Nothing inherently wrong about skepticism there. The only problem being.. the irony of the second or third opinion those folks would actually need from a neurologist, psychologist, and psychiatrist in all other matters.

(Sorry about the long post folks, I really get fired up when I see links like that, and all I think about is some noob who is emotionally swayed by it, who knows no better, and is led down another direction where voodoo runs rampant. I was almost there when I got into audio, and only stumbled by here accidentally, as I assumed audio was just like computers for example, where benchmarks and validation ran supreme, and not people 'feels').
 
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Kal Rubinson

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Judging by the sheer number of media reported long term 'scientific studies' that appear to re-iterate the bleedin' obvious, I've come to the conclusion many scientists desire lucrative commission work, and will happily take on anything, if it pays the bills. :)
I get your point. However, scientists do not fund their research out of their own pockets. Funding can come from many sources (institutional, governmental, commercial, etc.) but, fundamentally, it is motivated by desire/need for the information. In a sense, all research is commissioned.
 
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