You didn't quite get my drift but knowing John for more than 40 yr. it is not productive to elaborate. There is the path of knowing everything full well but proceeding anyway, because the world has passed you by.
I have great respect for Vanderkooy's and Lipshitz's contribution as published for example in the JAES (and in fact learned a lot from then when joining the AES while I was studying) but wrt the underlying problems of objective testing,I'm sorry, but Lipshitz was more than once undestimating the difficulties or gave just misleading recommendations.
It needed Leventhals article about sufficiently statistical power in any experimental procedure to allow further conclusions from results and Lipshitz finally admitted it in his JAES article from 1990, but he still seemed unable to realize what profound impact the often highly artificial test conditions can have on the participants performance.
His recommendation /1/:
"It is usually best, rather than conducting a preset number of trials, to monitor the statistics as the trials proceed, and to extend the number of trials if there appears to be a reasonable possibility that a subject is performing better than random."
is a good example of introducing a procedure with high risks of contorting the real result.
/1/ Stanley P. Liphsitz; The Great Debate - Some Reflections Ten Years Later; AES 8th International Conference: The Sound of Audio (May 1990), Paper No. 8-016
Thank you for this, it is not a paper of which I was aware. I have some reading to do!
Nevertheless we shouldn't underestimate the effects of training and expertship and of course although surely not infallable an expert will always apply a lot of certainty to his findings.
Although it is an interesting question which way the expert status is established, it is often in other sensory departments (taste for example) so that experts were asked and if the expert says "the effect is really small" than controlled rigorous double blind procedures were used.
Which does not mean that experts are working without controlled conditions.
I've emphasized quite regularly that learning to listen is mandatory for doing perceptual evaluations.
Thank you for the reference to Stanley Lipshitz's paper - it is an interesting read, characteristically well-written and thoroughly recommended to anyone interested in the discussion in this thread. I am not sure I agree that there was anything with which Lipshitz did not realise, however - at least not by the time he wrote that paper. I also took the opportunity to revisit Leventhal's papers for the first time in 30 years or so.
What struck me from my reading/rereading was the lack of mention of linearity in the test subjects - at least any explicit acknowledgement of such. Methods were discussed that took account (or not) of the variability in listener's response as per some random influence, instead of attempting to account for their non-linearity due to their ability to learn to resolve information in time - real or otherwise.
Notably too, Lipschitz emphasises that discerning an audible difference is not the same as stating which is "better". As an example, I remember one hi-fi journalist who constantly resorted to the bass at the introduction of Rickie Lee Jones' Easy Money and the audibility of the string fingering: Simply adding EQ in the right place (or stumbling across a loudspeaker with the right frequency response deviations) could produce a "better" report.
Indeed. But we need also be wary of "expertship" in the absence of objective verification. As I have tried to express in my contributions, there exists a significant possibility of delusion and for affirmation of that delusion thereafter. How can one who prides him/herself on their listening ability say they are unable to hear what another "expert" can hear, for example? It does not imply dishonesty or even stupidity, it is instead a consequence of the way we are destined to respond.
It doesn't, that is the point. Mastering engineers have actually learned to notice small aberrations in recorded music and do so with very high (but imperfect) reliability.
However, to a dogmatic observer who has has a knee jerk reaction to label virtually all skilled listening as delusion it might be perplexing to see so many presumed deluded people hearing things most people would fail to hear.
How do they do it? Some combination of natural ability, years of training, and regular practice.
Here at diyaudio, we have quite a few people who appear to me have some undeveloped natural ability. Bob is an example of someone who has developed his abilities more than most have.
Also, Scott, you may remember PMA who was once very much in the 'people claiming to hear small imperfections are deluded' camp. Over time and with ongoing practice he developed some listening skill, and finally heard something he shouldn't have been able to. He was able to confirm that he was hearing something real using ABX. However, the experience left him with a first hand understanding of why ABX has such poor sensitivity and why it tends to requiring exhausting concentration. Before that he would dismiss anyone else's claims of ABX insensitivity as lame excuse. Only finding out firsthand for got through to him what's wrong with ABX and why non-deluded skilled listeners may fail at it.
Over time I have developed my own belief that the process PMA put himself through is probably they only way people like soundbloke will ever be able to truly understand what is auditory delusion and what is not. Right now he only thinks he knows. Every time he mistakenly declares someone else deluded it is his own delusion in believing his declaration to be true.
Who has said otherwise?
Who does have such a reaction? Who has labelled skilled listening as delusion?
You have once again failed to grasp the fundamentals of what I have said. Instead you have posted a "knee-jerk" reaction in which you offer nothing to rebut what I have actually said. How about you direct some effort at disclosing the innumerable errant assumptions you have stated that I have made?
About "why designing yet another dac"..
How many bits should a dac be able to convert to analog??
In an average listening room there is 20-30 dB "noise" constantly.
90-95 dB SPL when listening to music is pretty loud.
We are therefore able to hear no more than some 75-80 dB of musical information above noise floor.
16 bits is able to provide us with 96 dB of resolving power, so normally that shoud suffice.
Very good loudspeakers have less than 1% distortion, that a long shot away from 16 bit!
So, what are we worrying about?
IMO more important than these exotic specifications, well laid out interfaces, power supplies and I/V - analog stages is where quality can be gained for domestic music reproduction.
How many bits should a dac be able to convert to analog??
In an average listening room there is 20-30 dB "noise" constantly.
90-95 dB SPL when listening to music is pretty loud.
We are therefore able to hear no more than some 75-80 dB of musical information above noise floor.
16 bits is able to provide us with 96 dB of resolving power, so normally that shoud suffice.
Very good loudspeakers have less than 1% distortion, that a long shot away from 16 bit!
So, what are we worrying about?
IMO more important than these exotic specifications, well laid out interfaces, power supplies and I/V - analog stages is where quality can be gained for domestic music reproduction.
Do you have some objective evidence of either of these statements.
Where is the list of the things you should not be able to hear?
Always when I am listening critically. That is why I work to establish what is real and what is not.
And you are the only one who could possibly put in the effort to establish what is real or not?
Yes Matt I hope to put some light on it but not expecting much more than this as far as acceptance is concerned.
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Where have I ever indicated anything that amounts to that??? I merely point out that some on here that appear unaware of the inherent fallibility that is apparent in us all, and of the non-trivial task of ameliorating it.
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