You couldn’t hear the difference - Proof! Beautiful video of David Mellor (Audio Masterclass) about sound differences between DAC

[DanielT]

So is the concern that signal A has passed through X number of devices vs signal B the same X plus a mediocre DAC so because of that you can't compare A vs B because of these X? Why couldn't we do that?

 

[JiiPee]

In my previous post, I wrote that far too many threads on this forum have descended to a fruitless back and forth argumentation. I don't fancy myself participating to one, so I will restrain myself from responding to this thread anymore.

 

[solderdude]

The device is basically a microphone A/D converter (makes sense to use one to create videos like he does). He lists links for EVERYTHING he uses for his videos. Teleprompters, microphones, monitors. Even what he uses for hair care. No link to say device he used for the "test". You are making assumptions. The questions is about equipment used. The video author makes no mention (except your "link") is being ambiguous at best, even when faced with a direct question in the video comments, the author does not answer. Perhaps ambiguity is his intention, if for aything but to generate activity such as this thread.

I understand blind A/B testing and the principle behind it.

But as a music listener, this test is irrelevant. If the goal is to point out "you cannot tell the difference between DACs" then it is pure BS depending on what you call a "DAC". I am not going to be listening to music through a mic A/D converter. And of all the two-channel "DACs" intended for music, take any two and you will probably hear a difference (design and gain stages make a difference, chips? no so much, but I have had my share of "bad" sounding "DAC" purchases). This is what I suspect MOST on this forum are interested in. Not some 48+Khz sampling pro audio device.

No offence or insult taken. It is just irritating that so many assumptions are made based on a post of two or three sentences (and how "new" I am to this forum). Attempting a broader view/understanding of the world may help (no gaurantee), but I am not here to give advice.

In any case the video is useless as far as I am concerned.

This is what the guy did:
He took an original recording which was made at Abbey Road studio. He played back the recording on the (mediocre performing) UMC202HD and looped the analog output to the analog input of the same UMC202HD and recorded that signal so he got the original recording (digital file from Abbey Road) + the same music but it went through a cheap DAC-ADC loop.

Can you tell the difference between an original Abbey Road recording and that same recording through a mediocre DAC?

So there are 2 digital files. 1 original and one that went through cheap DAC/ADC process.

The things we don't know:
Was the original source digitally attenuated ?
What was the analog 'input level' set to ?
I assume that he time aligned and level matched the 'looped' file digitally in his DAW.
That would be a definite requirement simply because of the delay in the DAC + ADC process and the loopback is analog and went through a MIDAS pre-amp set to minimal gain.
Then created the file where he toggled between original (Abbey Road) recording and the DAC-ADC loop of mediocre quality.

(B.t.w. I also own UMC202HD and UMC204HD among other DACs and DAC/ADC)

The point he was making that even when you have an original super high quality recording from Abbey Road studio and loop that through a cheap and not great performing DAC + ADC you cannot tell the difference whether or not the signal is 'pure' or went through a cheap audio device.

And... I am sure you could not pass the test either so you too could not detect when the recording was original or the original that went through a cheap DAC+ADC.

Here is the thing ... we have to trust the guy that what he said he did was what he actually did and was not out to trick people and either did not switch or he just loaded 2 original files in his DAW but simply renamed one pretending to have gone through cheap DAC-ADC.

So for you the video is pointless because you either did not understand the test or it is pointless because you could not hear a difference so it is 'trickery'.

 

[Geert]

So for you the video is pointless because you either did not understand the test or it is pointless because you could not hear a difference so it is 'trickery'.

Like the most popular counter argument in the video comments; ”The test is invalid because we don’t listen to DAC loops” That's like; ”I don’t believe my arthritis diagnosis because we don’t run in MRI scanners”.

 

[DanielT]

The laziest counterargument, that is, to dismiss the test by claiming that it is just made up/trickery.

Why would he make it up? If you look at videos that David Mellor (Audio Masterclass) made fifteen years ago, you can say with 100% certainty that he is recording.Fifteen years ago and since then he has continued with it, and other things related to music and Hifi, resulting in 450 videos.
He has access to a studio, he has the equipment, he has the recording knowledge so why the hell would he lie about this mediocre DAC loop test?

Check this out, which shows David Mellor's credibility:


Those were just a few examples.Here is the rest:

Audio Masterclass

David Mellor's (that's me!) Audio Masterclass is your go-to channel for all things audio, from hi-fi and home recording to professional sound. I dive deep into the world of high-fidelity audio, explore the latest gear, and share insights on how to get the best sound in any environment. Whether...

youtube.com

Edit:
The questions @solderdude asks in #83 The things we don't know:....are absolutely ok and sensible to ask. It's possible that they have already been addressed and answered in the comment section of his Youtube video. But I don't know, there are over 600 comments there.

 

[Svend P]

And of all the two-channel "DACs" intended for music, take any two and you will probably hear a difference

Not in a proper blind test:

How can DAC's have a SOUND SIGNATURE if they measure as transparent?

I know there are people out there that think cables affect sound, which is much worse, but there really is no response to something like that, but just to smile and nod. But what about people who talk about DACS as if they were headphone drivers or speakers, and talk about the SOUNDSTAGE...

www.audiosciencereview.com

 

[ahofer]

And of all the two-channel "DACs" intended for music, take any two and you will probably hear a difference (design and gain stages make a difference, chips? no so much,

The evidence strongly suggests otherwise, as I have repeatedly pointed out, with links. And you still don’t have your facts straight about the test in question, as amply demonstrated above.

This test appears to be a valid test of whether the introduction of one cheap ADC/DAC in the signal chain changes the signal audibly. The answer, predictably for those of us who took @blumlein ‘s 8-loop test, is no. But there are dozens of other tests, and a large body of audiological knowledge, that suggest your assertion above is incorrect. Alas, I repeat myself.

 

[danadam]

The whole thing is flawed and the opposite of a blind test, it´s a self-fulfilling scenario.

Given that his test was trivially easy to cheat, I'm not sure what is self-fulfilling here.

Here is the thing ... we have to trust the guy that what he said he did was what he actually did and was not out to trick people and either did not switch or he just loaded 2 original files in his DAW but simply renamed one pretending to have gone through cheap DAC-ADC.

We can check if he did something. And yes, he did and switched forth and back six times, as he said:

So we still do not know this mystery device he used for the test. Or if it even resembles a typical DAC an "audiophile" would use to listen music. We just know that is cheap and on amazon.

This complaint would only make sense if you also claimed that audiophiles typically use much worse DACs than the one he used. Is that what you say?

When you listen to the file he provided then what you compare is:

• the original file --> your DAC (presumably good) --> your ears

to:

• the original file --> his DAC (cheap) --> his ADC (cheap) --> your DAC (presumably good) --> your ears

When you don't hear the changes then there are three explanations (one of them not really serious):

1. His cheap DAC and ADC introduce so little distortion that the changes are below audibility. Therefore the DAC --> ADC steps are transparent. Therefore his cheap DAC on its own is even... er... transparenter
2. Your DAC (presumably good) is in fact really bad and the distortion it introduces, hides any changes introduced by his cheap DAC and ADC.
3. (not really serious) His DAC introduces big changes but his ADC somehow magically reverts them.

So which one is it? (I know, "He didn't use the music I like" )

 

[ahofer]

When you don't hear the changes then there are three explanations (one of them not really serious):

1. His cheap DAC and ADC introduce so little distortion that the changes are below audibility. Therefore the DAC --> ADC steps are transparent. Therefore his cheap DAC on its own is even... er... transparenter
2. Your DAC (presumably good) is in fact really bad and the distortion it introduces, hides any changes introduced by his cheap DAC and ADC.
3. (not really serious) His DAC introduces big changes but his ADC somehow magically reverts them.

Wish I could like this twice.

There are other explanations - the switching is faked/it’s a better DAC. But, whatever.

 

[solderdude]

We can check if he did something. And yes, he did and switched forth and back six times, as he said:

clear evidence, mostly added noise by the DAC-ADC loop.

Indeed, which the video set out to show, even if a budget ADC and DAC would make any audible difference then you should be able to hear this in this file using high quality gears and ears.
When you can't ... you can't.
The good thing is that it is quite measurable (with the right tools) but obviously not audible.

 

[DanielT]

Given that his test was trivially easy to cheat, I'm not sure what is self-fulfilling here.


We can check if he did something. And yes, he did and switched forth and back six times, as he said:

View attachment 447063


This complaint would only make sense if you also claimed that audiophiles typically use much worse DACs than the one he used. Is that what you say?

When you listen to the file he provided then what you compare is:

• the original file --> your DAC (presumably good) --> your ears

to:

• the original file --> his DAC (cheap) --> his ADC (cheap) --> your DAC (presumably good) --> your ears

When you don't hear the changes then there are three explanations (one of them not really serious):

1. His cheap DAC and ADC introduce so little distortion that the changes are below audibility. Therefore the DAC --> ADC steps are transparent. Therefore his cheap DAC on its own is even... er... transparenter
2. Your DAC (presumably good) is in fact really bad and the distortion it introduces, hides any changes introduced by his cheap DAC and ADC.
3. (not really serious) His DAC introduces big changes but his ADC somehow magically reverts them.

So which one is it? (I know, "He didn't use the music I like" )

Good job. Thanks for showing what the music file looked like.

Wish I could like this twice.

There are other explanations - the switching is faked/it’s a better DAC. But, whatever.

You should be able to see the positive in the fact that you can't hear any differences. I mean, hurray now I don't have to buy that extremely expensive DAC, those cables that cost like a car, those ...choose whatever nonsens...to get that superb sound and can instead spend my HiFi money on what really matters; speakers, room acoustics, EQ and amplifier (modern sensible with a decent amount of power vs low powered high end tube amp).
But at the same time I understand that those who have invested a decent amount of money on, at worst, nonsense gadgets, really fight back and try to find explanations. Otherwise they would feel a bit stupid and cheated.

 

[krabapple]

And of all the two-channel "DACs" intended for music, take any two and you will probably hear a difference (design and gain stages make a difference, chips? no so much, but I have had my share of "bad" sounding "DAC" purchases).

Are DAC output stages commonly so variable in voltage as to be likely audible?

If not, the 'difference' you 'probably hear' is probably imaginary.

If so, we definitely do want to account for it, leaving us with just the 'sound' of the 'chips'.

Your 'broader view' is old, old hat here. This is why your 'newness' is being noted.

 

[livinon2wheels]

It was good. Well done with music files to download. Check out the first video regarding the test:
View attachment 445808
Screenshot above from this video:

I have long maintained the fever over the extreme prices charged for some DACs to be just that...a fever and one that affects ones common sense and clearly ( to me ) most of the fuss over a $30k Dac vs my 329 Wiim is just people wanting it to sound better than my humble $329 Wiim because they paid more, but my ears cannot perceive any difference listening to the file you played to determine whether you switched between the loop-back version and direct version even once...not by just listening. With sophisticated measuring equipment I bet that I could, but I could not hear it. I consider myself a trained and refined listener, but at the end of the day, there is so much noise about such minute differences in sound quality that the price differential is huge. And to my practical mind and limited pocketbook the expensive gear is so much more about bragging rights than actual sound quality. I am delighted with my Wiim streamer DAC. And I may buy a second one for another location in my home. Its that good. I see no reason to spend more.

 

[DanielT]

I have long maintained the fever over the extreme prices charged for some DACs to be just that...a fever and one that affects ones common sense and clearly ( to me ) most of the fuss over a $30k Dac vs my 329 Wiim is just people wanting it to sound better than my humble $329 Wiim because they paid more, but my ears cannot perceive any difference listening to the file you played to determine whether you switched between the loop-back version and direct version even once...not by just listening. With sophisticated measuring equipment I bet that I could, but I could not hear it. I consider myself a trained and refined listener, but at the end of the day, there is so much noise about such minute differences in sound quality that the price differential is huge. And to my practical mind and limited pocketbook the expensive gear is so much more about bragging rights than actual sound quality. I am delighted with my Wiim streamer DAC. And I may buy a second one for another location in my home. Its that good. I see no reason to spend more.

Wiim has hit the bull's eye with its features.

Regarding DACs. I go for features, size and appearance. Where appearance matters the least.Size isn't really that important to me either, but it does matter a little.

DACs' sound performance itself, however, is a closed chapter. In the vast majority of cases, the measurable differences are far below the limit of audibility. In all cases, if we are talking about well-known brands, SMSL, Topping and so on. The usual suspects Amir tests, so to speak.

It is now just as interesting or more interesting to read about users' experiences. Is gadget X easy to use, does X work with Y if you want to do Z. Such practical things are of interest.

 

[livinon2wheels]

There is an old joke about why Italian sports cars have small rear view mirrors - 'because whats behind me doesn't matter' and if the noise and distortion inherent in a given piece of gear isn't audible then it also just doesn't matter anymore.