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If I may add one more explanatory note re: that "circumstantial" connection.

When Lipshitz in his AES article is writing that:

"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 [TL: the 24/24 score with test tones], and discern the polarity reversal on this signal with unvarying accuracy. Indeed, in a double-blind demonstration to eleven members of the SMWTMS audio group, the accuracy score was 100% on the summed 200-Hz and 400-Hz tones over loudspeakers [TL: again, that 24/24 test-tone score], 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 reversal is audible."

...he is indeed describing the very same test whose results are given in greater detail on the ABX comparator site. Compare the numbers; on the other hand, the 11 test participants are described more in the Audio Amateur article (though are of course also noted on the ABX comparator site). Lipshitz isn't famous for clarity and he is clearly struggling to avoid direct confrontation with the fact that with musical material the score was no better than 60/113.

The prob with the "cryptic" way of presenting the info on the ABX comparator site is that their system for doing so is actually a bit too basic. The line "Van der Kooy / Lipshitz Training Signal" gives the score obtained with the test tone (it was specifically designed for this purpose by the test authors); the line "Sheffield & Other Phonograph Records" gives the score obtained when music, not the test tone, was used ("phonograph records" were utilized as this was after all still the pre-digital era...). The last two lines report on further tests for which neither Lipshitz nor Vanderkooy were in attendance (not addressed by any of the articles discussing their "own" test, then). The columns giving the p value and the number of participants in each test round are self-evident.

In a word, all of these sources that have been mentioned talk about the the same test results (the ones whose closer numerical breakdown is given on the ABX comparator site but only more generally described in the papers referred to).

TL




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