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In Reply to: Poor old Ed Long, defending his own erroneous speaker designs. But NOTE BENE: posted by clarkjohnsen on May 9, 2007 at 08:43:29:
You said that your book was lauded in Audio Magazine, when reading E.E.Long's review, I don't get that impression. That was the very point I was trying to make.Obviously also DDD Shanefield has got it wrong being "polarity deaf" ? Again, someone who did not laud.
Btw., did you write a letter to the Editor to clarify all those issues you are mentioning here and now?
Klaus
Follow Ups:
.
No, why should I, everybody is entitled to have an opinion about your book.However, JA is misleading the reader when paraphrasing from Lipshitz' AES`paper on phase distortion : "Work by Stanley Lipshitz in the late '70s, using carefully organized double-blind testing, confirmed that a reversal of absolute signal polarity will be subtly audible on music to a 99% confidence limit."
Whereas the Lipshitz paper states the following: "The authors have demonstrated the TWO-TONE experiment described above to numerous people on different systems. No one has ever failed to hear the timbral change with phase, and discern the polarity reversal on this signal with unvarying accuracy. Indeed, in a double-blind demonstration to 11 members of the SMWTMS audio group, the accuracy score was 100% on the summed 200-Hz and 400-Hz tones over loudspeakers, and overall, including musical excerpts, the results on the audibility of the polarity inversion of both loudspeaker channels were 84 correct responses out of 137, this representing confidence of more than 99% in the thesis that acoustic polarity is audible."
I suggest that the original text is radically different from what JA writes in his "as wee see it". Deliberately or not, JA is providing misleading information to the reader.What was the score of that part of the DBT where musical excerpts were used?
Klaus
So "subtly" it can't even be heard:
See link for the actual results of the study Atkinson was referring to. With music the score was 60 / 113 = 53%. That can reflect the result of mere guessing and provides of course no proof whatsover of any audibility; rather the opposite in all likelihood is the case.
That is, unless Atkinson is referring to another study by Stan Lipshitz that I'm unaware of. Barring that, why grossly misstate the results?
TL
...the audibility of Absolute Polarity on music. You choose to ignore his record here. Why?Of course we all know why!
It contradicts your erroneous case.
Also you continue to ignore Dr. Heyser. Why?
Because you have to!
Nor have you provided us yet with a scientific definition of "convincing" and "solid".
Looks rather hopeless, having a rational dialog with someone who dismisses the evidence.
clark
What were the scores of that part of the DBT where musical excerpts were used? THAT would be evidence that is interesting and relevant for consumers. THIS seems to be the only evidence obtained by Lipshitz, however, without a score, what do we know about the value of that evidence? I do not ignore his record, just tell us what the score was and we talk further!
Since we are speaking of presenting misleading information, tu quoque, filii:In your AES convention paper, page 13:
"The authors have demonstrated the TWO-TONE experiment described above to numerous people on different systems. No one has ever failed to hear the timbral change with phase, and discern the polarity reversal. Indeed, in a double-blind demonstration, the accuracy score was 100% [on a two-tone test] over loudspeakers, and overall, including musical excerpts, the results on the audibility of the polarity inversion of both loudspeaker channels represented confidence of more than 99% in the thesis that acoustic polarity is audible."
What you have omitted here is that, overall, only 84 out of 137 reponses were correct. How many response were correct when musical excerpts were played?
Further, in a letter to Audio Magazine 1994 that passage was further reduced to:
"In a double-blind demonstration....including musical excerpts, the results on the audibility of the polarity inversion of both loudspeaker channels represented confidence of more than 99% in the thesis that acoustic polarity is audible."You didn;t even mention that part of that confidence was based on TEST TONES.
What evidence? There's that Lipshitz SMWTMS audio group DBT of which the score is not known and that's about it.
I don't count all those experiments where artificial signals were used for obvious reasons. I don't count your own experiments for the reasons outlined before.
Klaus
Sufficient to say, their experiments satisfied them as to the efficacy of Absolute Polarity in bringing us all "Better Sound for Free", and they did not hesitate to trumpet this discovery to the world from every location they commanded.Pity the world won't listen.
clark
Do you have a Cassandra complex, Clark?
Clark, try and read carefully what I write.B.F.Muller, "Third World: The Scientific Subjectivist, Audio Amateur, vol. 11, p.64 (1980 Jan.).
Lipshizt, A little-understood factor in A/B testing, Boston Audio Society speaker, vol. 6, (1978 March)
Lab books indeed!
Klaus
> You said that your book was lauded in Audio Magazine, when reading E.E.Long's review, I don't get that impression. That was the very point I was trying to make.Hey, they gave it two pages and a color photograph.
> Obviously also DDD Shanefield has got it wrong being "polarity deaf"? Again, someone who did not laud.
Dan Shanefield is one of only two people on record (so far as I know), besides yourself, who dismiss absolute polarity. Besides which, Dan has been outright rude to my face -- not a pleasant person.
I notice that you have nothing to say about Atkinson, Cockroft, Heyser et al. Perhaps just as well, for you.
> Btw., did you write a letter to the Editor to clarify all those issues you are mentioning here and now?
No. I was advised that Ed Long was their golden boy at that time and they wouldn't print it. Besides, the review sold a few hundred copies, and who am I to disagree with success?
Klaus
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