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Topic: lecture: Critical listening/evaluation - a path to the future of quali (Read 92495 times) previous topic - next topic
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lecture: Critical listening/evaluation - a path to the future of quali

Reply #25
I attended the lecture last night.

Quite a mixture.


George was quite shy / intimidated by the standing-room-only crowd in the hall. He'd set up 2 ATC monitors, Prism converters, Pro Tools, and an Arcam DVD-A player at the front.

I believe the two multi-tracks he played are available via bit torrent. The other recordings he played (and much of the evening was spent listening) were 192kHz 24-bit stereo masters - some unreleased tracks, some recent and not so recent ones. All good recordings.

Too loud, too reverberant, and sat too far back - it's not how I'd choose to listen to music. The reproduction was about as far away from believing the singer was really in the room as you can get. I think the recordings and system were probably great, but who can judge in that environment at listening levels that make your ears ring?


George had some very interesting and sensible things to say about the recording of music. He said he didn't have an agenda, but really wanted to make people think. So he talked about capturing performances "as live" - tell the musicians they're not going to get the chance to punch in - if they do a re-take, it wipes the previous one. Put them all in the same room so that they can see and hear each other - the isolation of putting them all in padded boxes lets an accountant some along and demand you change the bass player next month, but it doesn't let you capture the best performance.

Take time to work out the subtleties of the music, and capture them properly. Good recordings with these subtleties still have more to give on the hundredth listen, decades after they were first recorded.


However, there was plenty said that would make most people here on HA seethe. The start was a look at some codecs, playing 192/24 vs 128kbps mp3 (ProTool High Quality - is that FhG based?) - and playing the difference signal - i.e. subtracting the original from the downsampled > encoded > decoded > upsampled version. He played a lot of examples of the noise added by the codec, saying "how can we do this to music?".

A question from the floor pointed out that an all-pass filter would give an even larger difference signal, but create little or no audible difference (hence the method is flawed in terms of illustrating the audible difference) - George doubted this example.

He also explained how he taught people to listen for artefacts by listening to original, coded, difference - over and over again on a particularly tricky part of the track - until they could hear the artefacts in the coded version.

This is a reasonable approach - but the question was never asked "what if they can't hear a problem with the coded version, despite knowing how much noise has been added?" - the impression was that any added noise was bad - "I can get 1.5Mbps over my DSL - stream that - there's no need to even go down to 256kbps AAC".


George was very unhappy about this paper (which we've discussed at length on HA):
http://www.aes.org/e-lib/browse.cfm?elib=14195
The discussion about ABX testing brought out the usual straw men. Interestingly, George and Peter (not sure which Peter!) had written a letter to the AES journal criticising the Meyer and Moran paper, which "they refused to publish". He said they'd asked the wrong question.


George wasn't using a microphone, and asked that no-one was recording because he was playing some pre-release tracks which he didn't want to get onto the internet. I don't know if an mp3 without the musical content will find its way onto the AES website - I'm going to ask.

Cheers,
David.

lecture: Critical listening/evaluation - a path to the future of quali

Reply #26
George was very unhappy about this paper (which we've discussed at length on HA):
http://www.aes.org/e-lib/browse.cfm?elib=14195
The discussion about ABX testing brought out the usual straw men. Interestingly, George and Peter (not sure which Peter!) had written a letter to the AES journal criticising the Meyer and Moran paper, which "they refused to publish". He said they'd asked the wrong question.


The letter to the JAES was cosigned by George Massenburg, Peter Craven, Vicki Melchior, and Wieslaw Woszczyk and was indeed rejected for publication, though John Vanderkooy did set up the on-line forum mainly as a result of the internal debate at the AES over the content of the letter.

Thank you for posting the report, David.

John Atkinson
Editor, Stereophile


lecture: Critical listening/evaluation - a path to the future of quali

Reply #27
George was very unhappy about this paper (which we've discussed at length on HA):
http://www.aes.org/e-lib/browse.cfm?elib=14195
The discussion about ABX testing brought out the usual straw men. Interestingly, George and Peter (not sure which Peter!) had written a letter to the AES journal criticising the Meyer and Moran paper, which "they refused to publish". He said they'd asked the wrong question.


The letter to the JAES was cosigned by George Massenburg, Peter Craven, Vicki Melchior, and Wieslaw Woszczyk and was indeed rejected for publication, though John Vanderkooy did set up the on-line forum mainly as a result of the internal debate at the AES over the content of the letter.


Why are these guys writing letters when one simple ABX test with positive results would do far more to advance their case?  Just one so-called hi-rez wav file of regular music that won't let itself be downsampled without easy detection, that is all it would take.  Look at the collection of hi-rez files that Atkinson must have. Not one will ABX from its 44/16 self with a positive result? Not one?

The explanation is simple - even though they claim the difference is obvious, the so-clalled obvious difference magically goes away when people are forced to discern differences by just listening. 

We have been here many times  before - one example involed talking to plants, and then there was cold fusion.

lecture: Critical listening/evaluation - a path to the future of quali

Reply #28
Quote
However, there was plenty said that would make most people here on HA seethe. The start was a look at some codecs, playing 192/24 vs 128kbps mp3 (ProTool High Quality - is that FhG based?) - and playing the difference signal - i.e. subtracting the original from the downsampled > encoded > decoded > upsampled version. He played a lot of examples of the noise added by the codec, saying "how can we do this to music?".


That's a shame.  It's the same bogus demo John Atkinson is 'educating' people with in his essay. GM loses some respect from me for that ..talk about 'asking the wrong question'!

And if he has to play a the difference sample 'over and over and over' in order to train people to hear mp3 artifacts...doesn't that tell him something about how easy it is to make mp3s that *don't* sound bad?

lecture: Critical listening/evaluation - a path to the future of quali

Reply #29
The letter to the JAES was cosigned by George Massenburg, Peter Craven, Vicki Melchior, and Wieslaw Woszczyk and was indeed rejected for publication, though John Vanderkooy did set up the on-line forum mainly as a result of the internal debate at the AES over the content of the letter.



which is here btw

lecture: Critical listening/evaluation - a path to the future of quali

Reply #30
If you are really interested in my thoughts and not just trolling, read my essays at [Stereophile]

I'll read through them, though I do wish they weren't quite so wordy.

BTW John, you have often been shown to hear whatever you want to hear...
Really? A specific example would be helpful, Mr. Krueger. This is HA, after all, where expression of opinion [is] required to be supported with evidential data.

Only with respect to statements related to matters of subjective sound quality, John

lecture: Critical listening/evaluation - a path to the future of quali

Reply #31
George was very unhappy about this paper (which we've discussed at length on HA):
http://www.aes.org/e-lib/browse.cfm?elib=14195
The discussion about ABX testing brought out the usual straw men. Interestingly, George and Peter (not sure which Peter!) had written a letter to the AES journal criticising the Meyer and Moran paper, which "they refused to publish". He said they'd asked the wrong question.


The letter to the JAES was cosigned by George Massenburg, Peter Craven, Vicki Melchior, and Wieslaw Woszczyk and was indeed rejected for publication, though John Vanderkooy did set up the on-line forum mainly as a result of the internal debate at the AES over the content of the letter.


Why are these guys writing letters when one simple ABX test with positive results would do far more to advance their case?  Just one so-called hi-rez wav file of regular music that won't let itself be downsampled without easy detection, that is all it would take.


Members of a private mail list that includes the above authors of the letter, as well as many other AES illuminati, have been having an active discussion about designing such a test. Far being it simple as you suggest, Mr. Krueger, it seems very difficult to design a test where the _only_ variable is the sample rate _alone_. Without that being attained, the test produces noisy results, with potential false positives as well as false negatives. Of course, if you are only concerned with obtaining a null result, the design of the test becomes much easier, vide the Meyer-Moran paper. :-)

John Atkinson
Editor, Stereophile


lecture: Critical listening/evaluation - a path to the future of quali

Reply #32
The start was a look at some codecs, playing 192/24 vs 128kbps mp3 (ProTool High Quality - is that FhG based?) - and playing the difference signal - i.e. subtracting the original from the downsampled > encoded > decoded > upsampled version. He played a lot of examples of the noise added by the codec, saying "how can we do this to music?".


I know that this is a trick performed by a lot of people who hate on lossy. What happens, I ask naively, if you take such a difference signal and subtract it from the original signal. Does it end up being something like the lossy encode? Would that be an example of how much information you can throw away without making an audible difference? Or does it not work like that?

lecture: Critical listening/evaluation - a path to the future of quali

Reply #33
The start was a look at some codecs, playing 192/24 vs 128kbps mp3 (ProTool High Quality - is that FhG based?) - and playing the difference signal - i.e. subtracting the original from the downsampled > encoded > decoded > upsampled version. He played a lot of examples of the noise added by the codec, saying "how can we do this to music?".


I know that this is a trick performed by a lot of people who hate on lossy.


Yes, it is like failing the qualification exam for Y2K audio production techniques.  If you get why subtrasction is a bad idea, then you have somehow figured out some useful stuff about how modern audio works. If you think subtraction is a relevant test, then you badly need a technical update class. 

Ironic that widely-respected dudes like Atkinson and Massenberg make such a big public show of stepping in this doggy-do-do on the sidewalk. Their feet smell of the do-do.  Many well-informed teenagers (and older) smell the stink. Guys who were once hip now make themselves look like clueless old turkeys.

Life lesson:  Part of growing older is watching some of your heroes start looking like bozos.

Warning about life lesson: its not always what it seems, but in this case it very much appears to be exactly what it seems. Sad.

Quote
What happens, I ask naively, if you take such a difference signal and subtract it from the original signal.


Or add it. Doesn't much matter.

Do the math.

O = original,  R = recording, and D = O - R.  Then R + D = R + O - R = O,
and

O -  D  = O - O + R  = R

Quote
Does it end up being something like the lossy encode?


Something like.

Quote
Would that be an example of how much information you can throw away without making an audible difference?


Yes, but the idea that you can throw something away is anathema to people who believe that the problem with modern recordings is what is being thrown away.

And at one point they are right. What's wrong with modern recordings *is* what is being thrown away.

The current problem *is* that the throwing away happens *before* the sound is converted into an electrical signal.

After all these many years of there being many faults with the handling of the electrical signal, they can't get the idea that the handling of the electrical signal is good enough that the remaining problems are elsewhere.  In fact we can handle the electrical signal with considerably but stategically-designed slop (we call this slop modern lossy compression), and get away with it.

lecture: Critical listening/evaluation - a path to the future of quali

Reply #34
I'm fairly new around here. I don't think I'm as "objectivist" as many here, as I simply have no patience for running ABX tests and listening for insignificant differences when I could be listening to music. I know I don't have the technical knowledge many of you have, as I don't quite understand some of what you're saying. Still, I'm driven here because the nonsense I was reading (and not hearing) on many audiophile forums was maddening. The language is laughable -- musical, euphonic, PRaT -- music is musical, and PRaT? As if your equipment can affect timing of the performance? I sometimes wonder if the inventors of such terms are sad, would-be musicians unsatisfied with their passive role in the art. But the language doesn't need to cross over into such absurdities to be highly suspect. I can't even count the number of times audiophiles and even professional reviewers have referred to the performance of components with simple terms like "muddy" or "harsh," and while these are vague enough, we all pretty much understand that the former means attenuated highs, the latter boosted ones (or distortion associated with them). These are simple characteristics that, if they can be heard, could easily be measured and reported on as distortion  and/or frequency response.

But they almost never are.

I think, ultimately, listening is subjective. If you like attenuated highs and rich (distorted) mids, that's fine with me. Buy valves and be happy. If you like exaggerated highs and the illusion of detail they create, I'm good with that too. Buy some Naim gear and speakers with nice metal tweeters; that should do the trick. I won't even require that you ABX test it if it makes you happy. The trouble is, the audiophiles I've run into on most of these boards aren't satisfied with being happy. They have to be right. They have to tell me that their personal choices in tone are the more natural reproduction of the source material.

And I just shake my head in wonder...

When it comes from someone like Mr. Atkinson, I shake my head a bit sadly. He has the resources at his disposal. If he hears muddy, he can verify it and report on it in meaningful terms. He not only has that ability, he has that responsibility. I don't know which came first, the lazy editorial content or the lazy engineering, but somewhere along the line, most of the "high-end" abandoned the pursuit of high-fidelity in favor of the pursuit of tone wrapped in elegant industrial art. And in the meantime, it seems that much of the "mid-fi" has passed them by. If accuracy and transparency is my goal, I would trust an integrated amp from Cambridge Audio or Yamaha (just a couple of many examples, I'm sure), far above the overwhelming majority of high-end audiophile products.

How sad is that?

Sorry for the long post. I needed to get that off my chest.


Tim

lecture: Critical listening/evaluation - a path to the future of quali

Reply #35
The letter to the JAES was cosigned by George Massenburg, Peter Craven, Vicki Melchior, and Wieslaw Woszczyk and was indeed rejected for publication, though John Vanderkooy did set up the on-line forum mainly as a result of the internal debate at the AES over the content of the letter.



which is here btw



I checked the link and found 9 comments about "Audibility of a CD-Standard A/DA/A Loop Inserted into High-Resolution Audio Playback".  I see none by the authors listed about.

What am I missing?

lecture: Critical listening/evaluation - a path to the future of quali

Reply #36
The language is laughable -- musical, euphonic, PRaT -- music is musical, and PRaT? As if your equipment can affect timing of the performance?


Try experimenting with a traditional analog compressor or expander. While, of course, the timing of the notes isn't affected, the listener's _perception_ of that timing can be by such a device. See also http://www.stereophile.com/reference/23 .

And, of course, lossy compressors set to low bit rates can affect the perceived rhythm of the music. The transient information will be smeared in time. In the recent blind comparisons of uncompressed and lossy-compressed music that I performed at public seminars in Colorado - see the "Why We Need Audiophiles" thread for details -  the listeners in 10 separate presentations in 3 different cities spontaneously offered words like "lifeless" "uninvolving," and "flat" to describe the lowest-rate version after the test had concluded, all of which suggest a change in the music's perceived dynamics and/or rhythm.

Quote
When it comes from someone like Mr. Atkinson, I shake my head a bit sadly. He has the resources at his disposal. If he hears muddy, he can verify it and report on it in meaningful terms.


I do try to correlate the sonic descriptions of the audio components we review with their measured performance, extensively. Perhaps you are you not a regular reader of Stereophile? If not, you can find a glossary of the descriptors used in subjective reviewing in a consistent manner in Stereophile at http://www.stereophile.com/reference/50/ .

But to address your point, the problem is that even a simple descriptor like "muddy" can be due to many different measured errors. It could be due to a loudspeaker cabinet panel resonance, an internal air-space resonance, an underdamped woofer alignment, a response aberration due to a power amplifier with a pathologically high output impedance, an unfortunate coincidence between the tuning frequency of the speaker's woofer/port and a room resonance, a high level of even-order harmonic distortion at low frequencies, and on and on...or even to _all_ of these to a greater or lesser degree.

As this is the case for every descriptor, the task you wish for is not so simple or obvious as you seem to be suggesting.

John Atkinson
Editor, Stereophile

lecture: Critical listening/evaluation - a path to the future of quali

Reply #37
Quote
Try experimenting with a traditional analog compressor or expander. While, of course, the timing of the notes isn't affected, the listener's _perception_ of that timing can be by such a device.


Well, given that what audiophiles and reviewers are typically talking about when they use the term PRaT is things like amplifiers and DACs, not the effects of analog studio gear, I'm not sure this is relevant. And even then, I'm almost certain that the use of the terms "pace, rhythm and timing" are inappropriate on the verge of absurd. Thousands of musicians have learned material off of cassette decks and turntables, devices so imprecise that instruments had to be re-tuned slightly to even play along, and it didn't degrade their ability to follow the pace, rhythm and timing of the music in the least.

Quote
And, of course, lossy compressors set to low bit rates can affect the perceived rhythm of the music. The transient information will be smeared in time.


There we go...there was already a term for the minor effects you're talking about...transient response. So why do you suppose the audiophile community felt compelled to invent a new, self-important and grossly imprecise term? What is it about precision of measurement and language that does not fill their needs?

Quote
I do try to correlate the sonic descriptions of the audio components we review with their measured performance, extensively. Perhaps you are you not a regular reader of Stereophile?


Glad to hear it. No, I'm not a regular reader. I was in the old days, of Julian Hersch (sp?) and Stereo Review. You guys lost me along the way, coincident, I think, to my discovery that pro studio gear handily out-performed much of the stuff that you were enthusiastically recommending at many times its cost.

Quote
But to address your point, the problem is that even a simple descriptor like "muddy" can be due to many different measured errors.


Yes, and what I'm suggesting is that they be described in relation to their causes and by their effects. In other words, rather than simply saying something sounds muddy, which is pretty meaningless, say that the pathologically high impedance causes a frequency response dip of X db from X khz to X khz, resulting in...and then, as far as I'm concerned, you can characterize it as you please. Muddy. Gooey. Stanky. Once you've given me the cause and effect, have at it with the descriptive prose. But as I said, I'm not a reader. If you are already doing this in your reviews, I apologize for referring to your post in my original diatribe.

I'm sure you're right that what I wish for is not as simple as I'd like it to be, but it seems that this hobby gave it a much greater effort in the 70s than it does today, and that manufacturers responded by pursuing fidelity instead of style. A good thing, in my estimation. Maybe I've been reading too many forums and not enough professional reviews. This much I'm pretty sure of: I've been listening, and I'm left with the impression that music lovers would get as good, if not better performance from a $1000 CA or Yamaha as they would from most grotesquely expensive high-end gear. If your magazine is running the pricey boutique stuff head-to-head against the best of what audiophiles look down their noses at and call "mid-fi," comprehensively measuring them against each other, and framing your findings in the science and engineering of sound before you indulge in the kind of audiophile poetry I've seen so much of, sign me up for a subscription.

Tim

 

lecture: Critical listening/evaluation - a path to the future of quali

Reply #38
Quote
What happens, I ask naively, if you take such a difference signal and subtract it from the original signal.


Or add it. Doesn't much matter.

Do the math.


Well, the point of my question was that I know I don't know enough maths to do the math.

Quote
Quote
Does it end up being something like the lossy encode?


Something like.


Am I worthy of further explanation?

lecture: Critical listening/evaluation - a path to the future of quali

Reply #39
Quote
What happens, I ask naively, if you take such a difference signal and subtract it from the original signal.


Or add it. Doesn't much matter.

Do the math.


Well, the point of my question was that I know I don't know enough maths to do the math.

Quote
Quote
Does it end up being something like the lossy encode?


Something like.


Am I worthy of further explanation?



I am very, very sorry. I have 4 goals when I post (which I probably fail at terribly).

(1) *Not* talk over people's heads, talk down, or seem pompous.

(2) Be economical with my time and words because I do have a life, appearances notwithstaning.

(3) Not waste time with trolls and arrogant people, other than maybe to have a little fun.

(4) Do help people understand audio, and BTW help myself by learning from other people regardless of where they are coming from.

I did not consider the possibility that some people who post here might not be comfortable with any algebra. My bad.

O = original, R = recording, and D = O - R.

IOW, the difference (D) is  defined here to be  the origional (O) minus the recording ®.  That's a choice I made. If I say that the difference is the Recording minus the Origional, then that difference is inverted from what I said. No biggie.

Then R + D = R + O - R = O,

If I add my  Difference to the recording then I get back the Origional.

and

O - D = O - O + R = R

And if I subtract  my Difference  from the Original then I get the Recording, which I believe was your question.

So the answer to your question is "Yes".

lecture: Critical listening/evaluation - a path to the future of quali

Reply #40
Quote
I do try to correlate the sonic descriptions of the audio components we review with their measured performance, extensively.

this is the step where you should think twice.

Quote
even a simple descriptor like "muddy" can be due to many different measured errors. It could be due to a loudspeaker cabinet panel resonance, an internal air-space resonance, an underdamped woofer alignment, a response aberration due to a power amplifier with a pathologically high output impedance, an unfortunate coincidence between the tuning frequency of the speaker's woofer/port and a room resonance, a high level of even-order harmonic distortion at low frequencies, and on and on...or even to _all_ of these to a greater or lesser degree.

dear HA readers could think that the words like this may be related to specific phenomena;
http://dictionary.classic.reference.com/browse/egotism

smokey pokey,
HA, very important
video-section coordinator

edit: better url
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lecture: Critical listening/evaluation - a path to the future of quali

Reply #41
Quote
I do try to correlate the sonic descriptions of the audio components we review with their measured performance, extensively.

this is the step where you should think twice.


Thank you. I was merely pointing out to "tfarney" that a) he was suggesting something that the magazine already does, to the extent that it is possible, and b) his criticism was not actually based on firsthand knowledge of the magazine's content.

Quote
Quote
even a simple descriptor like "muddy" can be due to many different measured errors. It could be due to a loudspeaker cabinet panel resonance, an internal air-space resonance, an underdamped woofer alignment, a response aberration due to a power amplifier with a pathologically high output impedance, an unfortunate coincidence between the tuning frequency of the speaker's woofer/port and a room resonance, a high level of even-order harmonic distortion at low frequencies, and on and on...or even to _all_ of these to a greater or lesser degree.

dear HA readers could think that the words like this may be related to specific phenomena;
http://dictionary.classic.reference.com/browse/egotism


My apologies,but I fail to see the connection between my posting and your comment. Assuming that you are not just making an ad hominem comment, are you suggesting that the measurable aberrations I listed do _not_ have any correlation with a listener's description of a sound being "muddy" (the specific descriptor mentioned by "tfarney")? Of course they do, but to pin down _which_ is actually the culprit could take considerably more time than is possible for a monthly review magazine. If you read Stereophile's reviews, you will see that we a) describe the sound quality of a component, using a consistent and transportable terminology as listed in the article I linked to, and b) we comment on the measured performance where that might suggest possible reasons for the sonic description. Why would anyone have a problem with that?

John Atkinson
Editor, Stereophile

lecture: Critical listening/evaluation - a path to the future of quali

Reply #42
Quote
If you read Stereophile's reviews, you will see that we a) describe the sound quality of a component, using a consistent and transportable terminology as listed in the article I linked to, and b)...

sorry, i can't read that...., now if this was web only, you would be forgiven, but you are actually killing trees to print that...
PANIC: CPU 1: Cache Error (unrecoverable - dcache data) Eframe = 0x90000000208cf3b8
NOTICE - cpu 0 didn't dump TLB, may be hung

lecture: Critical listening/evaluation - a path to the future of quali

Reply #43
The letter to the JAES was cosigned by George Massenburg, Peter Craven, Vicki Melchior, and Wieslaw Woszczyk and was indeed rejected for publication, though John Vanderkooy did set up the on-line forum mainly as a result of the internal debate at the AES over the content of the letter.



which is here btw



I checked the link and found 9 comments about "Audibility of a CD-Standard A/DA/A Loop Inserted into High-Resolution Audio Playback".  I see none by the authors listed about.

What am I missing?



'here' meant 'the forum is here', not, 'the letter is here'.


lecture: Critical listening/evaluation - a path to the future of quali

Reply #44
And, of course, lossy compressors set to low bit rates can affect the perceived rhythm of the music. The transient information will be smeared in time. In the recent blind comparisons of uncompressed and lossy-compressed music that I performed at public seminars in Colorado - see the "Why We Need Audiophiles" thread for details -  the listeners in 10 separate presentations in 3 different cities spontaneously offered words like "lifeless" "uninvolving," and "flat" to describe the lowest-rate version after the test had concluded, all of which suggest a change in the music's perceived dynamics and/or rhythm.


To actually affect the perceived rhythm of a track the smearing would have to pretty damn bad.  And *dynamics* is something else completely. Your demo was dubious for reasons cited already. What codecs, what rates, what samples were used? How were listener and presenter bias accounted for? Was this before or after the bogus and *highly* biasing 'look a what MP3s leave out!' demonstration?

Quote
When it comes from someone like Mr. Atkinson, I shake my head a bit sadly.


You're not the only one, tfarney.


lecture: Critical listening/evaluation - a path to the future of quali

Reply #46
Members of a private mail list that includes the above authors of the letter, as well as many other AES illuminati, have been having an active discussion about designing such a test. Far being it simple as you suggest, Mr. Krueger, it seems very difficult to design a test where the _only_ variable is the sample rate _alone_.


Only in some people's minds. No doubt the real problem is political, laced with a heavy dose of fear of the dark, along with fear of unfavorable illumination.

Quote
Without that being attained, the test produces noisy results,


If the goals for the test have not been attained, how can there be any discusison of results?

The only noise I hear is silence from people who can't back up their claims with a practical test that proves their point.

So-called Hi-rez recordings have been on the market for over 5 years, thousands of titles have been released, and yet nobody can come forward with even one example of a recording that sounds unambigiously different when cleanly downsampled.

Quote
... with potential false positives as well as false negatives.


IOW people are using the classic strategy for keeping the test from ever happening - demanding perfection.

Quote
Of course, if you are only concerned with obtaining a null result, the design of the test becomes much easier, vide the Meyer-Moran paper. :-)


As usual John, you're ignoring all of the vocal claims from your side of the fence that the audible benefits of higher sample rates are so obvious that only nearly deaf people listening to horrifically made recordings on incredibly bad systems, can't hear them.

The fact of the matter John is that you can't provide a hi-rez example of a typical kind of musical recording with none of the usual tricks that your side likes to pull like evaluating the end of a fade-out starting at -40 dB, or using a recording where the peaks are at -40 dB, etc.,  that can't survive downsampling without there being an audible difference.

Of course, in any fair evaluation, your side won't be able bring their favorite crutches, like sighted evaluations, unmatched levels, and non-sychronized comparisons.

IOW, ethical and mental cripples need not apply.

lecture: Critical listening/evaluation - a path to the future of quali

Reply #47
Quote
If you read Stereophile's reviews, you will see that we a) describe the sound quality of a component, using a consistent and transportable terminology as listed in the article I linked to, and b)...

sorry, i can't read that...., now if this was web only, you would be forgiven, but you are actually killing trees to print that...


I did give the link to the Web reprint of the article earlier in the thread: http://www.stereophile.com/reference/50/ .

And the Web archive has currently approaching 1000 reviews that illustrate the point I was making: http://www.stereophile.com/equipmentreviews/ .

John Atkinson
Editor, Stereophile


lecture: Critical listening/evaluation - a path to the future of quali

Reply #48
And, of course, lossy compressors set to low bit rates can affect the perceived rhythm of the music. The transient information will be smeared in time. In the recent blind comparisons of uncompressed and lossy-compressed music that I performed at public seminars in Colorado - see the "Why We Need Audiophiles" thread for details -  the listeners in 10 separate presentations in 3 different cities spontaneously offered words like "lifeless" "uninvolving," and "flat" to describe the lowest-rate version after the test had concluded, all of which suggest a change in the music's perceived dynamics and/or rhythm.


To actually affect the perceived rhythm of a track the smearing would have to pretty damn bad.


It doesn't have be dreadful, just enough to be noticed. Tony Faulkner wrote an article on this subject in the January 2009 issue of HiFi Critic, BTW. Worth reading.

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Your demo was dubious for reasons cited already.


Why was it dubious? Levels were matched precisely, the lossy compressed and sample-rate-reduced files were reconverted to 24 bits and 88.2kHz sample rate so that the DAC would be behaving identically with all the examples.

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What codecs, what rates, what samples were used? How were listener and presenter bias accounted for?


I have answered all your questions before, Mr. Sullivan, in the "audiophiles" thread. Either I can cut'npaste my reponses or you can do the work of looking them up for yourself. (My preference is for the latter.)

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Was this before or after the bogus and *highly* biasing 'look a what MP3s leave out!' demonstration?


You mean like George Massenburg's? Because many more people signed up for my demonstrations than the organizers had predicted, I had to omit that example. The demo of lossy compression consisted of 2 parts: first a "learning" section, where I identified which was the full resolution file and which was the data-reduced file and pointed out aspects of the sound that had changed; second, a single-blind section, using a different piece of music, which followed Phil Hobbs' protocol, where the data density was progressively reduced through the 5 minutes of the piece. The listeners were not aware of what they were listening to and  stood to the side, out of the line of sight while the music played. At the conclusion of the presentation, I asked them to describe what they heard. Almost everyone said they felt the sound got worse, as I described, no-one felt it sounded better as the piece progressed..
 
Feel free to disregard the results. But around 200 audiophiles took part in the 10 sessions, which meant that all the listeners could get a good sound, and the overall reaction was very positive, in that people appreciate learning things heuristically under non-threatening conditions.

John Atkinson
Editor, Stereophile


lecture: Critical listening/evaluation - a path to the future of quali

Reply #49
Members of a private mail list that includes the above authors of the letter, as well as many other AES illuminati, have been having an active discussion about designing such a test. Far being it simple as you suggest, Mr. Krueger, it seems very difficult to design a test where the _only_ variable is the sample rate _alone_.


Only in some people's minds. No doubt the real problem is political, laced with a heavy dose of fear of the dark, along with fear of unfavorable illumination.

<snip.

As usual John, you're ignoring all of the vocal claims from your side of the fence that the audible benefits of higher sample rates are so obvious that only nearly deaf people listening to horrifically made recordings on incredibly bad systems, can't hear them.

The fact of the matter John is that you can't provide a hi-rez example of a typical kind of musical recording with none of the usual tricks that your side likes to pull...IOW, ethical and mental cripples need not apply.


Is it really not possible for you to discuss anything without maintaining a barrage of ad hominem statements, Mr. Krueger? The people involved in this effort are hardly "ethical and mental cripples," but include several AES Fellows, some university professors, some well-known recording and mastering engineers, and even JJ. And no-one involved, least of all me, has made any accusations of deafness, or having "incredibly bad systems," or using "horrifically made recordings" about people like you who claim not to hear any advantage from bit depths greater than 16 or sample rates higher than 44.1kHz. Those are projections on your part.

John Atkinson
Editor, Stereophile