ABX Double Blind Test Results: Polarity
SMWTMS ABX Test Results
Polarity
| Polarity | Result | Correct | p less than | Listeners |
|---|---|---|---|---|
| Van der Kooy / Lipshitz Training Signal |  |
24 / 24 = 100% | 0.0005 | 9 |
| Sheffield & Other Phonograph Records |  |
60 / 113 = 53% | 0.7 | 11 |
| Van der Kooy / Lipshitz Training Signal | |
123 / 128 = 96% | 0.0005 | N.A. |
| Lisa Cellucci Master Tape | |
75 / 141 = 53% | - | N.A. |
| The tests of absolute polarity were done on the original Quad electrostatic speakers. They were used in hope of minimizing the known potential problem of speaker distortion revealing polarity. The audibility of the Stan Lipshitz / John Van der Kooy polarity training signal was confirmed on those speakers. However the audibility of polarity on music was not confirmed whether the sound source was vinyl or a 1/4" 2-track master tape I recorded of a soprano recital with piano accompaniment. Stan and John came to Detriot for the first pair of tests. The system included a Hartley 24" subwoofer, Leach amplfiers, an ARC SP3-1, and a Kilmanas modified Rabco turntable. |
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The different symbol means it is unlikely the percent correct score occurred by chance and thus the null hypothesis was disproven, which substantiates a real difference in sound quality. |
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The same symbol means that it is likely the correct score occurred by chance, the null hypothesis is not rejected, which means no difference was found. It does remain possible a difference may be substantianted with further testing. |
Send questions or comments on the ABX Web Page to David Carlstrom.