325/324
Interval information |
Thoyoyo comma
reduced
(Shannon, [math]\sqrt{nd}[/math])
S10 / S12
The marveltwin comma, 325/324, is a 13-limit (also 2.3.5.13 subgroup) comma measuring about 5.3 ¢. Its significance is in that it marks the difference between 16/13 and a stack of two 10/9's, or between 13/9 and a stack of two 6/5's. It can also be expressed as (25/24)/(27/26) and (100/99)/(144/143), among other expressions.
Being a triangle superparticular, it factors neatly into (625/624)(676/675). Other factorizations are (385/384)(2080/2079), (364/363)(3025/3024), (352/351)(4225/4224), and (351/350)(4375/4374). In the 17-limit it additionally factors into (595/594)(715/714).
Temperaments
Tempering out this comma leads to the rank-5 marveltwin temperament, which identifies 16/13 by two 10/9's stacked and enables marveltwin chords. The most significant further temperament is to temper out 625/624 and/or 676/675, equating 26/25 with 25/24~27/26. This in the 2.3.5.13 subgroup is the rank-2 cata temperament.