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Topic: lecture: Critical listening/evaluation - a path to the future of quali (Read 96922 times) previous topic - next topic
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lecture: Critical listening/evaluation - a path to the future of quali

Reply #151 –
Quote from: krabapple on
Mr. Atkinson, your claims about this 'dem' have been spread over two threads.


I haven't made any claims as such, Mr. Sullivan. I have offered descriptions of the dems in response to questions from you and others.

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You are the one who touted it as a demonstration of something.  It has been a chore getting a full description of your 'dem' from you, and even now aspects of it remain unclear.  So please don't get cranky when I suggest responses be kept pertinent and comprehensively informative to the questions asked.


I have now three times described the purpose of of these presentations, Mr. Sullivan. For a fourth time: I wanted the listeners to audition hi-rez PCM data under optimal circumstances, mainly using the 24-bit/88.2kHz masters of my own commercially released CDs, and I was also interested in exposing listeners to various data-reduced formats so that they could decide for themselves whether hi-rez formats are necessary, whether CD is good enough for serious listening, and whether the lossy versions are sonically compromised or not.  I also demonstrated how miking and mixing techniques affected the listener's perception of the recorded soundstage. I have described all the relevant details; I fail to grasp what "remains unclear" to you and, frankly, I am not concerned.

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All you have done in the most recent reply to me is refer me to previous posts in this thread, all of which raised methodological questions of their own, which were not fully answered.  The purpose of the 'progressive' degradation demo , and whether it was actually perceived as such, remains unclear; the reason given for using an obsolete codec were frankly, lame;  the role of expectation bias in the 'results' was essentially unaddressed, and the means by which subject response was gauged, seems spotty as described.


All in your opinion, Mr. Sullivan, and as I have said before, I see no point in arguing with other's opinions. That I disagree with your characterizations is all that needs to be said, I would have thought.

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As for not trying to 'prove' anything,  the first mention of your 'dem' on this thread ((post #37)) was  as evidence that low bitrate lossy affects perceived 'rhythm' and 'dynamics' of a track.  If not to support a point, why would you mention it at all?


I offered it as anecdotal support for the point being made in response to a question from another poster. It certainly wasn't intended as "proof," otherwise I would have identified as such. The word "proof" was your own interpolation, Mr. Sullivan, again it seems a pointless exercise for me to argue in support of the words you put in my mouth.

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As to what I "seemed to think,"  I wrote back in April on HA (on April 26, 2009, 10:40am, in the "Why We Need Audiophiles..." thread) in response to the questions you were putting to me at that time what my motives were: I wanted the listeners to audition hi-rez PCM data under optimal circumstances...


It cannot possibly have been 'optimal' listening conditions, as described...


Why not? The system was top-class, the rooms were acoustically well-designed and _very_ quiet and as I have already mentioned, I eliminated as many interfering variables in the comparisons as was possible. Yes, having up to 20 listeners at a time in the room meant that only a fraction could be optimally seated to perceive the stereo imaging, but as I sadi, the public turnout was much larger than anyone had predicted.

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Let me try to phrase this in a way that you cannot possibly wiggle away from on specious semantic grounds  (a mighty challenge, btw)


Ah, the obligatory cheap shot...Seriously, as a professional and successful writer I choose the words I use with care and I do try to convey the maximum meaning in the most direct manner. That you regard my comments as "wiggling" on "specious semantic grounds" does suggest that I have failed to achieve that goal. But as I said above, what I _do_ refuse to address are the many instances where you, or others like Arny Krueger, have put words in my mouth by saying that if I said "A," then I must have meant "B." Please note that if I said, "A," then "A" was what I meant. If the meaning of "A" escapes you, then you either didn't read what I wrote carefully enough or you didn't comprehend it.

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You still seem to think that your dem offered a valid means to compare whether hi-rez formats were better than CD, and whether lossy versions are sonically compromised.


Yes. Having had considerable experience of demonstrations organized by others over the many years I have been involved in this subject, I think that the circumstances of these demonstrations were of appropriately high quality for differences, if they existed, to be perceived.

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However, you do not claim anything was proved by it.

Correct?


That is correct. I have now 4 times offered my motives for doing these demonstrations and the related goals. Those goals were met. But as "proof" of anything? I have no idea whether the answers to the questions I listed were overall positive or negative, nor does the outcome concern me. As I have repeatedly told you, these werent' formal double-blind tests nor have I claimed they were - that was a projection by other posters - nor was there any scoring nor did I tally any results. All I was doing was allowing listeners to hear under optimal conditions the examples I had prepared, which they wouldn't have had access to otherwise,  and to decide for themselves whether there were differences that were important to them or not.

John Atkinson
Editor, Stereophile

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

Reply #152 –
I'm bemused by the hostility to JA on this particular point.

I mean, he played 128kbps CBR FastEnc after some other stuff, and some people described the quality as going down hill.

It surprises me that people heard a difference a) because it's hard to set up a system in a room and let lots of people hear decent audio from it, and b) because most people are deaf and/or don't care and/or don't know what to listen for.

Both both of those factors can be overcome - if this happened, is anyone really surprised that people heard the quality go down hill?

(Not to mention, I'm not following properly, but I'm guessing the encoder was FhG FastEnc - I think the non-buggy versions are good for CBR, but at least two different buggy versions are available, and either of these would be painfully obvious).


You can't extrapolate at all that the CD quality stuff sounded worse than 24/96 - but as described, the 128kbps mp3 was played last - if that was the only thing that sounded different, the quality would still have been heard to "go down hill".

Cheers,
David.

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

Reply #153 –
Quote from: 2Bdecided on
I'm bemused by the hostility to JA on this particular point.

I mean, he played 128kbps CBR FastEnc after some other stuff, and some people described the quality as going down hill.


But while you and I might understand what different codecs can mean and how they can 'skew' a demosntration...Mr. Atkinson apparently did not explain that to his audience. And the 128kps presentation was not the only 'dem' Mr. Atkinson claims to be performing -- it purported to compare four different levels of sound quality, though it is unclear what he told the audience in this regard.  Nor does his method rise to HA standards for a 'dem' of even 128kps quality.  So why the bemusement? You should be kinda 'hostile' too, to such flimflammery.  I can't see it helping *clarify* the relationship of mp3 sound to lossless, in the minds of 'audiophiles', it can only prejudice them more.

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It surprises me that people heard a difference a) because it's hard to set up a system in a room and let lots of people hear decent audio from it, and b) because most people are deaf and/or don't care and/or don't know what to listen for.

Both both of those factors can be overcome - if this happened, is anyone really surprised that people heard the quality go down hill?


There is a third factor in this 'dem' -- it's hard to determine if people really heard the difference, or whether they were primed to expect some audible degradation between start and end.  If an audience is primed to hear a difference , is anyone really surprised that they do?

And if the dem was presented as described, would anyone be surprised if the listeners 'decided' that mp3 'typically' sounds that way in 2009? 

Are you comfortable with someone presented as an authority on audio, 'educating' listeners in such fashion? If so, count *me* as the one bemused.


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(Not to mention, I'm not following properly, but I'm guessing the encoder was FhG FastEnc - I think the non-buggy versions are good for CBR, but at least two different buggy versions are available, and either of these would be painfully obvious).


According to Mr. Atkinson, the codec was the one supplied with Audition 1.0.  That makes it a FgH codec from no later than 2003. 

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You can't extrapolate at all that the CD quality stuff sounded worse than 24/96 - but as described, the 128kbps mp3 was played last - if that was the only thing that sounded different, the quality would still have been heard to "go down hill".



Indeed, a point I made previously (though Mr. Atkinson attempted to twist it): no one here disagrees that a 128kbps encode COULD sound worse than its lossy source...and all here would agree there are good and bad ways to demonstrate this, as well as ways to help 'ensure' that a difference is audible to the average listener (like, bringing the bitrate down really low..or using a 'killer' sample...or using a bad codec at a middling bitrate...none of these would be a fair 'dem' of how mp3 'sounds'.)

We have no details on how long each segment was, but we know that the 128kbps segment followed a 320kbps segment (same codec), and that both had been reconverted back to wav, then upconverted to 88.2/24 bits.  We know that subject responses didn't come until after the whoel track was played; we know that responses weren't tallied.  We know that some number felt the music sounded 'lifeless' afterwards.

We know that Mr. Atkinson presented this a demonstration of some sort (still unspecified as to what JA actually told them before he played to tracks) for the listeners to 'decide for themselves'.

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

Reply #154 –
Quote from: krabapple on
Are you comfortable with someone presented as an authority on audio, 'educating' listeners in such fashion? If so, count *me* as the one bemused.
I'm not "comfortable" with JA's last two decades' work.

I just don't see the point of picking this demo apart in detail. It's a demo which some people will claim or infer proved a lot, but in fact proved nothing. I think we got that point a while back


Now, here's an interesting thing: the demo in the lecture that this thread is nominally about was even more flawed. You can listen to the discussion in the link I provided.

I was in that audience. There were a few hundred people there - my guess is only five of us realised a) it was flawed, and b) the audio would have had real deficiencies that could have been ABXed over headphones, but any differences that people thought they heard in that public listening environment were almost certainly imagined.

99% of the people there accepted that mp3 sounds awful (full stop!), that the difference signal accurately demonstrated how awful it sounded, and that they could really hear a clear difference between the original and the mp3 over speakers in a hall with several hundred people. Oh, and that ABX testing is fundamentally flawed.

This wasn't the audiophools subjectivists society - this was the audio engineering society.

You see, there's more serious work to be done than arguing about a JA demo.

Stereophile might just be a symptom, rather than a cause.

Cheers,
David.

EDIT: The reason I mind the debate about JA's lecture is because JA is a master debater, and solicits spiteful sounding responses which make HA look weak and unfriendly. The responses are born out of frustration and incredulity, not to mention truth and a trust in science, but a casual observer might think the opposite.

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

Reply #155 –
Master debater JA does have a charmingly parsimonious attitude towards doling out details, and a real talent for the semantic two-step, I grant him that.  I've tried to be polite about it, in a low pH sort of way.  In any case, we all seem to agree now that whatever his demonstration was supposed to be about, it can't honestly be said to have demonstrated much about hi rez vs CD vs 320 vs 128. 

I already weighed in twice on the tragic nature of Massenburg's demo, and I doubt listening to the lecture (which I plan to do) is going to make me more sanguine about it.  But he's not here defending it, while Atkinson came here, talking up his. If GM posted here, I don't doubt there would be some questions for him, and if he answered in Atkinsonian fashion, I don't doubt the questions would grow pointed.  However, he doesn't have Stereophile's illustrious history as a propaganda arm of the 'high end' attached to him, the way JA does, so perhaps it would be a less 'unfriendly' reception.  ( I also wonder what audience you are concerned about here...those casual HA observers...don't they *always* have a learning curve to attend to?)

Meanwhile, if you're an AES member, a letter to JAES expressing exactly the concerns you voiced above, is one possible recourse.  I would imagine JJ and any AES members that post regularly here, could have a dog in that hunt too.

(I'm still trying to reconcile how the AES can be run by a 'cabal' that censors critiques of Meyer & Moran's JAES article, yet also hosts demonstrations like Massenburg's. Sounds kinda schizo to me    )

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

Reply #156 –
Quote from: krabapple on
(I'm still trying to reconcile how the AES can be run by a 'cabal' that censors critiques of Meyer & Moran's JAES article, yet also hosts demonstrations like Massenburg's. Sounds kinda schizo to me    )
I don't think there's a cabal. I think there were many individual members at that meeting who work in the recording industry and unquestioningly accept more bits+samples = better. I think the Meyer & Moran paper solicited such a large number of responses that the AES decided to make an open forum on their website, rather than fill their publication with the discussion. I don't think there's an unseen or seen "controlling mind" - it's the sum total of its members.

I could be wrong.

Cheers,
David.

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

Reply #157 –
Quote from: krabapple on
There is a third factor in this 'dem' -- it's hard to determine if people really heard the difference, or whether they were primed to expect some audible degradation between start and end.  If an audience is primed to hear a difference , is anyone really surprised that they do?


Your problem with grasping what I did, Mr. Sullivan, appears to stem from your not reading what I wrote. You asked me about this aspect of the dem 3 days ago, in this thread, in the following exchange in message #85.:

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you say the listeners 'were not aware of what they were listening to' but what did the listeners know about the track they were listening to?


Nothing, other than it was a recording of Handel's Messiah.


There was nothing unclear about my response, nothing equivocal, nothing that would be hard to comprehend.

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We have no details on how long each segment was...


Again, all this information was included in my responses to your questions: the musical excerpt was from Handel's Messiah, identified as "For unto us a Child is born" in the article I linked to earlier in the thread. I told you that the excerpt lasted around 5 minutes and that there were four different versions spliced together, meaning that each segment was around 75 seconds. (The article I linked to explained why this musical piece was used, in that it had the same music repeated three time, meaning that each of the four segments was the same length and was comprised of the same content.)

Again, I fail to grasp why you feel that my description was incomplete. I am sorry to belabor the point, but you seem curiously incapable of reading what I actually took the time to write in response to your ongoing inquisition.

And to address a point you made in another posting:

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I'm still trying to reconcile how the AES can be run by a 'cabal' that censors critiques of Meyer & Moran's JAES article, yet also hosts demonstrations like Massenburg's. Sounds kinda schizo to me...


The AES is not a monolithic entity. It is comprised of people with differing points of views and experiences. I have been a member of the AES since 1981, but that doesn't mean that I necessarily agree with, for example, the conclusions of the Meyer-Moran paper.

John Atkinson
Editor, Stereophile

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

Reply #158 –
What sense does it make to argue anymore about Atkinson's show-biz demonstration?

It didn't even adhere to the most basic standards. It used a stone age mp3 encoder for the lossy demonstration, presented a difference between 16 bit and 24 bit at unemployable listening levels (that would show any thinkable amount of obviously wasted bits to be audible), mixed it up with non correlating sample rate differences, and it wasn't double blind.

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

Reply #159 –
Quote from: rpp3po on
It sed a stone age mp3 encoder for the lossy demonstration,

This is a common occurrence with people who think all MP3 encoders are bad, they don't differentiate between old and new encoders, because they assume that the format itself is inherently flawed to the extent that it has never been improved.

In fact, many don't even realise that different encoder versions effect quality.

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

Reply #160 –
Quote from: rpp3po on
What sense does it make to argue anymore about Atkinson's show-biz demonstration?

It didn't even adhere to the most basic standards. It used a stone age mp3 encoder for the lossy demonstration, presented a difference between 16 bit and 24 bit at unemployable listening levels (that would show any thinkable amount of obviously wasted bits to be audible), mixed it up with non correlating sample rate differences, and it wasn't double blind.


I'm prone to defend *any* demonstration that is presented as a demonstration on the grounds that it is just a demonstration. I used this argument with some  folks from Stereophile w/r/t an ABX-related demonstration that several of my friends put on at an AES meeting about 20 years ago. Even though the Stereophile folks still don't have the grace to agree with my viewpoint with respect to demos , I'm going to defend what George did on the same grounds as I defended what my friends did way back when. The asme argiment applies to what John did outside the AES.

It was a demo!

Obviously, there are demonstrations that are done well and there are crappy ones.  Anybody who looks for good science in demonstrations is IMO an optimist.

That all said, it is a very good thing when demonstrations are well-run and advance our understanding of how the universe really works. IOW, the demo is  as scientific as is possible, given the obvious limitations of demonstrations.

These demos do show as much if not more about the demonstrators than they do about their purported topics, which is actually very sad.

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

Reply #161 –
Quote from: 2Bdecided on
Quote from: krabapple on
(I'm still trying to reconcile how the AES can be run by a 'cabal' that censors critiques of Meyer & Moran's JAES article, yet also hosts demonstrations like Massenburg's. Sounds kinda schizo to me    )
I don't think there's a cabal. I think there were many individual members at that meeting who work in the recording industry and unquestioningly accept more bits+samples = better. I think the Meyer & Moran paper solicited such a large number of responses that the AES decided to make an open forum on their website, rather than fill their publication with the discussion. I don't think there's an unseen or seen "controlling mind" - it's the sum total of its members.


The various AES sectons run pretty independently. It would be hypocritical of me to criticize the AES for the latitude that the UK section is exercising, when the Detroit section had considerable latitude to do what we did with ABX way back when.

IMO  the UK section is running science backward, while back then the Detroit section ran science forward.  But not everybody agrees with that.

At the bottom of all this is people's personal perceptual models.

While there are big differences in the specific areas of human behavior involved, ABX (really the whole area of design of subjective experiments)  and perceptual coding share a common and very strong interest and have developed practical insights into the management of how people perceive things. 

The ABX insight was that memory and belief precondition how we perceive sound. The foundation of perceptual coding is the insight is that more external parts of the human hearing apparatus precondition how we perceive sound. There has been very strong synergism in the meeting of these two insights.

The people who rely on single blind and sighted evaluations are simply ignoring very much of what is known about the current model of human perception, especially regarding bias in the brain.

The people who rely on outdated coders and signal subtraction are again simply ignoring very much of what is known about the current perceptual model of human perception, especially regarding bias in the ears.

Therefore, that it would turn out to be the same people that ignore both of these important areas of our current perceptual model of human beings should be no surprise. They are trailing-edge traditionalists while we are far closer to the leading edge.

I suggest that we should have a moment of silence for our weaker brothers, some poorly-informed and some simply boneheaded.

Then we should get on with the rest of our lives which needs to include formulating effective stratgies for the poorly-informed to become informed. The boneheads will always be among us. ;-)

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

Reply #162 –
Quote from: rpp3po on
What sense does it make to argue anymore about Atkinson's show-biz demonstration?


None at all. It was what it was. I have no idea why Steven Sullivan has been obsessing about it or why he has such trouble comprehending what was a straightforward description of the conditions.

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It ...presented a difference between 16 bit and 24 bit at unemployable listening levels (that would show any thinkable amount of obviously wasted bits to be audible)


Please please read what I actually write. As I repeatedly mentioned, there were _no_ presentations of difference signals at last month's Colorado dems. That was George Massenburg in his London presentation (the nominal topic of this thread). Yes, I _did_ refer to a 2007 demonstration I had performed of the difference signal between hi-rez and Red Book versions of the data, but that was to show that at normal listening levels, the difference signal was _in_audible.

John Atkinson
Editor, Stereophile

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

Reply #163 –
Quote from: Arnold B. Krueger on
The foundation of perceptual coding is the insight is that more external parts of the human hearing apparatus precondition how we perceive sound.

Do you know if advances in perceptual encoders can be directly attributed to the development of a more sophisticated perceptual model?

For example, was the transition from MP3 to AAC based on new evidence of how humans perceive sound, or was AAC simply an attempt to fix known technical flaws in MP3?

Did we have a better model of human hearing when MP3 was developed, but had to dumb the specification down in order to make encoders that could work on early 1990s computer hardware? Or are all the bad aspects of MP3 related to the fact we just didn't know as much back in the 1980s about hearing that we know now?

I completely agree with you that the rejection of perceptual encoding is in effect a rejection of an aspect of human nature, specifically that human perception is in many ways flawed, and that consciousness itself is essentially an extremely elaborate series of perceptual illusions that - thanks to our large brains - interact in an extremely complex way.

Although they will never realise it, people who assume that lossy encoders are inherently flawed are effectively rejecting a fundamental aspect of human nature, that is the fact our senses aren't perfect, they just evolved over millions of years to provide us with roughly accurate information as quickly as possible. There are lots of other animals that have better smell, touch, hearing or sight than humans, but humans have flawed senses wrapped in a very sophisticated sense of self awareness. The sad thing is that some people refuse to apply that  sophisticated sense of self-awareness, to accept that their senses are flawed. They seem to assume that human hearing is in every way perfect, which therefore leads them to assume that there is no way possible that lossy encoders could work.

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

Reply #164 –
Quote from: Stereoeditor on
Yes, I _did_ refer to a 2007 demonstration I had performed of the difference signal between hi-rez and Red Book versions of the data, but that was to show that at normal listening levels, the difference signal was _in_audible.


This seems believable. The difference between a 16 bit version of a 24 bit file and the 24 bit file is always going to be smaller than the 16 bit version's LSB.  That in turn will always be 96 dB or more below peak level.  That will be masked in all but the quietest imagainable listening room. Certainly, in a conference presentation context, there is very, very little chance of it being heard.

Hence my previous comments about demos.

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

Reply #165 –
Quote from: Stereoeditor on
Quote from: krabapple on
There is a third factor in this 'dem' -- it's hard to determine if people really heard the difference, or whether they were primed to expect some audible degradation between start and end.  If an audience is primed to hear a difference , is anyone really surprised that they do?


Your problem with grasping what I did, Mr. Sullivan, appears to stem from your not reading what I wrote. You asked me about this aspect of the dem 3 days ago, in this thread, in the following exchange in message #85.:

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you say the listeners 'were not aware of what they were listening to' but what did the listeners know about the track they were listening to?


Nothing, other than it was a recording of Handel's Messiah.


There was nothing unclear about my response, nothing equivocal, nothing that would be hard to comprehend.


It's not a problem of not reading, thanks.  Possibly a problem of comprehending, since I am having trouble ,still, picturing exactly what 'went down', from you piecemeal descriptions so far.  So, showed up, did your 'listener training' dem (but not the difference demo, since you had no time), played that recording ,  and then asked 'so, what did that sound like'? And some unspecified number of people replied something like 'it sounded worse at the end than the beginning'.  Or was is 'It kept sounding worse and worse'?  So far you have only, AFAICT, described what some unspecified number spontaneously reported about the *last* presented segment -- the one with the most dubious codec use -- , calling it 'lifeless' and 'uninvolving'.

What, btw, was the title of your session, again?


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We have no details on how long each segment was...


Again, all this information was included in my responses to your questions: the musical excerpt was from Handel's Messiah, identified as "For unto us a Child is born" in the article I linked to earlier in the thread. I told you that the excerpt lasted around 5 minutes and that there were four different versions spliced together, meaning that each segment was around 75 seconds. (The article I linked to explained why this musical piece was used, in that it had the same music repeated three time, meaning that each of the four segments was the same length and was comprised of the same content.)


Ah, then the 'seamless' joins you mentioned earlier take on a different meaning too.  Software ABX tools have an option to either continue the track at the switch point, or go back to start.  I took your referfence to 'seamlessness' as the former sort of protocol.  So now, at  least , it is clear how they could have known when one segment ended and the other began.  We're making progress!

Really, sir, the question boils down to, as you must know it does:  when presented multiple versions of the same audio sample , was there anything to lead the audience to expect audible difference, other than the sound itself? To me , it  would seem curious on its face that John Atkinson would come and play me the same segment four times, if there *wasn't* some attempt to demonstrate audible difference in the offing.  And of course there's that 'listener training' preamble.


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Again, I fail to grasp why you feel that my description was incomplete. I am sorry to belabor the point, but you seem curiously incapable of reading what I actually took the time to write in response to your ongoing inquisition.


Or perhaps I am inclined to get you to put down the information here, in one place, and in as full detail as possible.  Is that so wrong?

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And to address a point you made in another posting:

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I'm still trying to reconcile how the AES can be run by a 'cabal' that censors critiques of Meyer & Moran's JAES article, yet also hosts demonstrations like Massenburg's. Sounds kinda schizo to me...


The AES is not a monolithic entity. It is comprised of people with differing points of views and experiences. I have been a member of the AES since 1981, but that doesn't mean that I necessarily agree with, for example, the conclusions of the Meyer-Moran paper.

John Atkinson
Editor, Stereophile


Tongue in cheek, sir, tongue in cheek.

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

Reply #166 –
Quote from: ShowsOn on
Quote from: Arnold B. Krueger on
The foundation of perceptual coding is the insight is that more external parts of the human hearing apparatus precondition how we perceive sound.


Do you know if advances in perceptual encoders can be directly attributed to the development of a more sophisticated perceptual model?


Some, but not all.

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For example, was the transition from MP3 to AAC based on new evidence of how humans perceive sound, or was AAC simply an attempt to fix known technical flaws in MP3?


AFAIK, both kinds of changes were involved.

You can find details about the genesis of various modern methods for perceptual coding here:

http://citeseerx.ist.psu.edu/viewdoc/summa...=10.1.1.26.5956 - on this page press the cached button in the upper right corner.

(BTW this is a JAES paper that can luckily be back-doored for free)


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Did we have a better model of human hearing when MP3 was developed, but had to dumb the specification down in order to make encoders that could work on early 1990s computer hardware? Or are all the bad aspects of MP3 related to the fact we just didn't know as much back in the 1980s about hearing that we know now?


I don't know.

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I completely agree with you that the rejection of perceptual encoding is in effect a rejection of an aspect of human nature, specifically that human perception is in many ways flawed, and that consciousness itself is essentially an extremely elaborate series of perceptual illusions that - thanks to our large brains - interact in an extremely complex way.


Rejection of modern subjective testing techniques is also a rejection of a what is now a well-known aspect of human nature.  My studies of DBTs shows that DBTs were well-understood and being applied to real world experiments no later than the early 1950s. DBTs were being applied to tests relating to hearing long and showing up in JASA articles long before we started doing ABX tests of audio gear. The JASA is significant because the study of acoustics is very close to audio, and both the JASA amd JAES are read by many of the same people.

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Although they will never realise it, people who assume that lossy encoders are inherently flawed are effectively rejecting a fundamental aspect of human nature, that is the fact our senses aren't perfect, they just evolved over millions of years to provide us with roughly accurate information as quickly as possible. There are lots of other animals that have better smell, touch, hearing or sight than humans, but humans have flawed senses wrapped in a very sophisticated sense of self awareness.


Totally agreed. This is all so well known that it is surprising that audio's high end can still get away with what they try to get away with.  Their model of hearing is that no only can we hear anything that is measurable, but there are things that we can clearly hear that are as yet immeasurable.


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The sad thing is that some people refuse to apply that  sophisticated sense of self-awareness, to accept that their senses are flawed. They seem to assume that human hearing is in every way perfect, which therefore leads them to assume that there is no way possible that lossy encoders could work.


I've listened to part of the Massenburg UK AES talk that relates to this. Now, this recording is so messsed up that for me, tying to get something out of it is more demanging than some ABX tests!  However, what I seem to hear him saying is that he justifies signal subtraction on the grounds that it has worked well for him in other areas.

IOW,  tradition rules his value system.

In a way, that is also what we seem to be hearing from Atkinson. After all, if sighted listening was good enough for JGH in 1958 or 1982, it is still good enough for SP in 2009.

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

Reply #167 –
Quote from: rpp3po on
What sense does it make to argue anymore about Atkinson's show-biz demonstration?

It didn't even adhere to the most basic standards. It used a stone age mp3 encoder for the lossy demonstration, presented a difference between 16 bit and 24 bit at unemployable listening levels (that would show any thinkable amount of obviously wasted bits to be audible)


Actually, he reports that he didn't have time to that.  So let's not accuse him of uncommitted sins.  It makes us look weak. 

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

Reply #168 –
Quote from: Arnold B. Krueger on
The people who rely on single blind and sighted evaluations are simply ignoring very much of what is known about the current model of human perception, especially regarding bias in the brain.

The people who rely on outdated coders and signal subtraction are again simply ignoring very much of what is known about the current perceptual model of human perception, especially regarding bias in the ears.

Therefore, that it would turn out to be the same people that ignore both of these important areas of our current perceptual model of human beings should be no surprise. They are trailing-edge traditionalists while we are far closer to the leading edge.



Which wouldn't matter and wouldn't be worth 'obsessing' about, as Mr. Atkinson now characterizes it, if they weren't seen as authorities on such matters...when they have proven (to us at least) that they are not.



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

Reply #169 –
Quote from: Stereoeditor on
None at all. It was what it was. I have no idea why Steven Sullivan has been obsessing about it or why he has such trouble comprehending what was a straightforward description of the conditions.


Now *that* is a bit of an overstatement.  And btw, when people use that awful 'it is what it is' construction, I reach for my gun.

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Please please read what I actually write. As I repeatedly mentioned, there were _no_ presentations of difference signals at last month's Colorado dems. That was George Massenburg in his London presentation (the nominal topic of this thread). Yes, I _did_ refer to a 2007 demonstration I had performed of the difference signal between hi-rez and Red Book versions of the data, but that was to show that at normal listening levels, the difference signal was _in_audible.



Your statements have been many, distributed over more than one thread,a nd have involved anecdotes about different events.  Some confusion is perhaps understandable, and I seem not to be alone in being not quite able to keep it all tied up in a nice package in my head.  I *have* been trying to get a complete picture in one place, but it's been a bit of a *dental* undertaking.

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

Reply #170 –
Quote from: krabapple on
Quote from: Arnold B. Krueger on
The people who rely on single blind and sighted evaluations are simply ignoring very much of what is known about the current model of human perception, especially regarding bias in the brain.

The people who rely on outdated coders and signal subtraction are again simply ignoring very much of what is known about the current perceptual model of human perception, especially regarding bias in the ears.

Therefore, that it would turn out to be the same people that ignore both of these important areas of our current perceptual model of human beings should be no surprise. They are trailing-edge traditionalists while we are far closer to the leading edge.



Which wouldn't matter and wouldn't be worth 'obsessing' about, as Mr. Atkinson now characterizes it, if they weren't seen as authorities on such matters...when they have proven (to us at least) that they are not.


The irony of Atkinson criticizing people for obsessing should not be lost on anyone! ;-)  We both know this is just more of his obfuscatory behavior.

The larger view is that this is just another example of one of the things that happens as we age - we find out that are heroes are clowns, or at least that they have feet of clay.

There is another trend I've noticed. It seems harder to motivate people who have had good sucess to move beyond the technology or other behavior patterns that they obtained that success with.

According to Wikipedia, Massenberg was born within about a year of me. I admit it - I've never done for/with audio what he has. Not even 0.1%.  Perhaps my lack of success motivates me to keep trying to learn.    ;-)

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

Reply #171 –
Quote from: krabapple on
Quote from: Stereoeditor on
Your problem with grasping what I did, Mr. Sullivan, appears to stem from your not reading what I wrote....There was nothing unclear about my response, nothing equivocal, nothing that would be hard to comprehend.


It's not a problem of not reading, thanks.  Possibly a problem of comprehending, since I am having trouble ,still, picturing exactly what 'went down', from you piecemeal descriptions so far. So, with no explanation or preamble, you just showed up, played that recording...


No, that is not what I described, Mr. Sullivan. Are you really this obtuse? The presentation involved my playing a number of recordings, including, immediately prior to the Handel, comparing one of my hi-rez masters with an lossy-encoded version. You know this because I have explained it to you several times.

I then, as explained previously, then informed the audience that I was going to play another excerpt, an extract from Handel's Messiah that had been recorded by Philip Hobbs of Linn. Period.

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... and then asked 'so, what did that sound like'? And some unspecified number of people replied something like 'it sounded worse at the end than the beginning'.  Or was is 'It kept sounding worse and worse'?  So far you have only, AFAICT, described what some unspecified number spontaneously reported about the *last* presented segment -- the one with the most dubioukls codec use -- , calling it 'lifeless' and 'uninvolving'.


I described the reaction of the listeners several days back, Mr. Sullivan. I refer you to that response.

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What, btw, was the title of your session, again?


You have already asked me this, Mr. Sullivan, and I offered you an answer. Do you really not remember?

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Again, all this information was included in my responses to your questions: the musical excerpt was from Handel's Messiah, identified as "For unto us a Child is born" in the article I linked to earlier in the thread. I told you that the excerpt lasted around 5 minutes and that there were four different versions spliced together, meaning that each segment was around 75 seconds. (The article I linked to explained why this musical piece was used, in that it had the same music repeated three time, meaning that each of the four segments was the same length and was comprised of the same content.)


Ah, then the 'seamless' joins you mentioned earlier take on a different meaning too.


Not at all. The splices between the four sections of the piece were seamless so that the listeners were presented with one continuous piece of music lasting around 5 minutes with no indication that anything was changing, other than the possible change in sound quality itself.

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Software ABX tools have an option to either continue the track at the switch point, or go back to start.  I took your referfence to 'seamlessness' as the former sort of protocol.  So now, at  least , it is clear how they could have known when one segment ended and the other began.


As I have repeatedly said but you don't appear to comprehend, Mr. Sullivan, there was _no_ overt indication that anything was changing. All the listeners knew was that they were listening to a recording of "For Unto Us a Child is born" from Handel's Messiah. That is the elegance of Philip Hobbs's protocol: there is no indication that anything is changing as the music progresses nor are the listeners aware prior to the audition that there is anything unusual about what they are about to hear. Thus there are no expectation biases.

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Really, sir, the question boils down to, as you must know it does:  when presented multiple versions of the same audio sample , was there anything to lead the audience to expect audible difference, other than the sound itself?


None. Nothing. On the face of things, the presentation of the Messiah excerpt was just another in a series of musical pieces I was playing as part of the presentation.

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To me , it  would seem curious on its face that John Atkinson would come and play me the same segment four times, if there *wasn't* some attempt to demonstrate audible difference in the offing.


It wasn't the same segment played four times. As explained in the article to which I linked and reiterated in the earlier response, Philip had chosen this piece of music because the same music  - not the same _segment_ - repeats three times. ie, there are 4 choruses. I used the same musical example as Philip because of this aspect of the music, ie, the audience would hear the chorus 4 times without being alerted by that fact that something unusual was happening, thus bypassing the expectation effect you mention.

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Or perhaps I am inclined to get you to put down the information here, in one place, and in as full detail as possible.  Is that so wrong?


It seems redundant given that you have random access to every posting I have made in this thread, offering the same answers to the same questions you keep coming up with, Mr. Sullivan. You have stated that you don't bookmark my responses, but if you are _really_ that interested in this subject and not just trolling, then I don't grasp why you are so resistant to doing the legwork and rereading those responses.

John Atkinson
Editor, Stereophile

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

Reply #172 –
Quote from: Stereoeditor on
Quote from: krabapple on
Quote from: Stereoeditor on
Your problem with grasping what I did, Mr. Sullivan, appears to stem from your not reading what I wrote....There was nothing unclear about my response, nothing equivocal, nothing that would be hard to comprehend.


It's not a problem of not reading, thanks.  Possibly a problem of comprehending, since I am having trouble ,still, picturing exactly what 'went down', from you piecemeal descriptions so far. So, with no explanation or preamble, you just showed up, played that recording...


No, that is not what I described, Mr. Sullivan. Are you really this obtuse? The presentation involved my playing a number of recordings, including, immediately prior to the Handel, comparing one of my hi-rez masters with an lossy-encoded version. You know this because I have explained it to you several times.


Actually, I edited that post within minutes of putting it up, to include note of the 'training' segment. Your reply certainly hadn't appeared yet.  It appears you ended up responding to the old version.

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

Reply #173 –
Quote from: ShowsOn on
I completely agree with you that the rejection of perceptual encoding is in effect a rejection of an aspect of human nature, specifically that human perception is in many ways flawed, and that consciousness itself is essentially an extremely elaborate series of perceptual illusions that - thanks to our large brains - interact in an extremely complex way.

I quite agree, but as this thread is all about rhetoric, it might be well to think about the language here. I'm not actually sure that it's right to say that human perception is "flawed": we don't hear as high frequencies as a bat, or as low volumes as a cat, but that's a selectivity, part of the complex evolved way we perceive the world. An awful lot of making sense of the world, surely, is "knowing" what to ignore. To make this practical, I have two recordings that drive me nuts: Glenn Gould's Bach Two and Three Part Inventions, in which his singalong is too present, and a lute album, which is beautifully recorded (despite the fact that they use a green substrate for the CD because it's an audiophile edition  ), but you can hear the mechanical noises of the lute to an extent that I find distracting. In both these cases, hearing less would not be a flaw. The microphone has supplemented a limitation of human hearing, not in a good way.

Equally, to talk about us having perceptual illusions is, I think, misleading, since this implies that we could, in some way, perceive the world in a disillusioned way (and this, probably, leads to the homunculus fallacy). Rather we must accept that the rather elaborately processed events in the brain are the way by which we perceive the world (unless you want to get PoMo on my ass).

This rhetorical point matters, because if one talks of "flaws" and "illusions" it suggests that some people might have perceptions that are less flawed, might have fewer illusions, and so leads to audiopholly and the shameless hucksters who feed it and profit from it.

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

Reply #174 –
Quote
None at all. It was what it was. I have no idea why Steven Sullivan has been obsessing about it or why he has such trouble comprehending what was a straightforward description of the conditions.


I find this back-and-forth about the conditions of the demo to be weird. There are way too many key variables in a demo situation to catalogue in a "straightforward description". Word choice and verbal intonation aside, even an unwittingly meaningful grin, glance, or reflexive audiophiliac wince or body tic at the transition points between the samples can throw the results off kilter. (A bit OT, but my collie uses eye contact to convey situational meaning in lieu of words, as dog owners may be able to relate.)

It thus strikes me as quite useless to try to extract real proof of anything from such demos. But in the white-room conditions of an ABX test, rhetorical sway and groupthink become useless and the ability to discriminate remains as the only thing that matters.