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Interval information
Ratio 27/25
Monzo |0 3 -2>
Size in cents 133.23757
Name(s) large limma
Color name gg2, gugu 2nd

[sound info]

27/25, called the large limma or acute minor second, at 133.238 cents, has the remarkable property of almost exactly equaling a singe step of 9edo, a step of which is 133 1/3 cents. Hence nine large limmas fall just short of an octave by the ennealimmal (meaning "nine limmas") which is |1 -27 18>, a comma of less than a cent in size. If all of that were not enough, two large limmas are almost exactly a subminor third, since (7/6)/(27/25)^2 = 4375/4374. Turning from microtempering to exotempering, 27/25 can be tempered out, leading to bug temperament, rather than the ennealimmal temperament which tempering out both the ennealimma and 4375/4374, the ragisma, leads to.

Coincidentally 27/25 is exactly three octaves below the ratio between 432hz and 50hz, common frequencies in tuning and AC electrical power respectively.