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RE: Then it seems neither do you.

OK. Let's go into this a little deeper, then, as you still seem to prefer to avoid addressing the points raised.

(1.) Where did you get the result that polarity reversal is audibile on music to a 99% confidence limit?

The latter applies to the overall results only: test tones and musical excerpts combined -- not music alone as you claim.

The quotation you refer to above is by a grad student at U Miami. Why don't you cite Lipshitz himself? Or any of the two sources you cited in your original Sphile article?

But let's stay with this "99% confidence limit" a little that you misattributed to the results on music (and that gives a misleading impression that polarity reversal is somehow audible on music):

The results obtained by Lipshitz & Vanderkooy were: 24/24 correct responses on test tones, and 60/113 correct responses on music. So we get the following as regards:

(i) Audibility on Test Tones:

24/24 has a 2*2^(-24) = 2^(-23) chance of occurring randomly (we should include 0/24, since that would be considered equally significant, which is why it's multiplied by 2) -- which is less than 1/1,000,000. So this result is highly significant, which no one denies: "Audible on test tones."

(ii) Audibility on Music:

On the other hand, the 60/113 score (or more) on music has about a 29% chance of occurring randomly, and if we use the two-tailed significance we must again multiply it by 2 -- so it has a greater than 50% chance of happening by guessing. In other words, no significance: "Not audible on music."

(iii) Audibility Overall:

Combining both data sets gives the score of 84/137, with a two-tailed significance of almost exactly 99%. Obviously, all the significance here comes from the test-tones results, as anyone can immediately see from the above.

(iv) Therefore it is indeed possible to say that overall, polarity reversal is audible with 99% confidence; and that it's audible on test tones with better than .000001 confidence; BUT it is NOT possible to say (like you do) that it is audible on music with any confidence at all.

So we can only conclude that your claim is totally false (either a misrepresentation or simply erroneous, I'm not sure as you have preferred not to clarify this).

In other words, the effect, as has been summarized by many already, if audible at all, is certainly "very subtle," given that no one thus far has been able to detect it in double blind tests on music (contrary to what you claim; but please feel free to cite evidence showing otherwise). Including Stan Lipshitz.

To repeat: You claim that polarity reversal is audible on music to a 99% confidence limit! (Exlamation mark and italics yours.) And that Stan Lipshitz has demonstrated this in his experiments discussed above. And that the audibility of polarity reversal on music is indeed one of the few things that can be reliably detected with double-blind testing (Italics yours).

None of these three claims are true, as we can all clearly see: There are no DBTs that show this audibility on music. The confidence level you cite was obtained by Lipshitz not for music but for overall score combining also test tones. Lipshitz himself couldn't establish any audibility on music, either. And if no one has shown it with DBTs, it obviously cannot be detected with them with any kind of reliability, no matter how flexibly you yourself might prefer to use the concept.

Seems clear enough? Or still uncomfortably black-and-white for your taste?

(2.) If it seems people like I keep "dredging around the facts" for too long (we actually like facts), why not put the matter to rest? You know what to do, since you've proposed it yourself: Edit that Sphile article to reflect the actual facts of that Lipshitz experiment, and issue a correction of this erroneous claim in Sphile as you've already said at least two or three times that you will. End of story.

(3.) As for the Sphile test CD, I have it and have run a few series of little experiments precisely with that polarity track. I am afraid my result may disappoint you (and I can assure you it's not because of my audio system is inadequate).

(4.) And as for those "efforts to undermine the questioner's character" that you deny, I obviously referred to your post in response to Robert Young in which, instead of addressing any matters of substance, you instead decided to try and raise doubts about my general competence and credibility in precisely those areas in which you now seem to be somewhat lacking yourself, if I may say so, judging from the above.

TL


Edits: 12/18/07
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