Mystery comma
Interval information |
mystery comma,
Pythagorean quadridietic semilimma
reduced subharmonic
[46 -29⟩, the 29-comma or mystery comma of 43.305 cents, is the difference between 46 octaves and 29 fifths, in other words 246/329. Because this comma is a Pythagorean interval and is almost exactly half of the traditional Pythagorean limma in addition to being a quadruple-diminished fourth, one can also call this interval the Pythagorean quadridietic semilimma.
Temperaments
Tempering out this comma splits the octave into 29 equal parts and maps the harmonic 3 to 17\29, leading to the 5-limit version of mystery temperament. For EDOs up to 400, the 29-comma is tempered out if and only if 29 divides it, for example 29edo, 58edo or 87edo.