In music, septimal sixth-tone is a septimal sixth-tone, an interval with the ratio of 50:49 ( play ), about 34.98 cents, which in just intonation is the difference between the lesser septimal (7:5) tritone, and its inversion, the greater septimal tritone (10:7). This interval is tempered out by 12-TET and 22-TET, but not by 19-TET, 31-TET or any other odd division of the octave.
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