170/169
Interval information |
Sothuthuyo comma
reduced
(Shannon, [math]\sqrt{nd}[/math])
170/169, the major naiadma, is a small 17-limit superparticular comma about 10.2 cents in size. It forms the difference between 13/10 (tridecimal semisixth) and 17/13 (large septendecimal semisixth). It is also the amount by which a stack of two 13/10s falls short of 17/10 (septendecimal major sixth). The name major naiadma is contrast to the minor naiadma, 221/220, measuring about 7.9¢, which is the difference between 13/10 and 22/17 (small septendecimal semisixth). They are so named because 13/10, 17/13 and 22/17 are naiadic interseptimal intervals, and 170/169 is larger than 221/220 by a 13-limit unnoticeable comma, 2200/2197 (petrma).
It is close to one step of 118edo and is tempered as such in the 118th-octave oganesson temperament, along with 169/168, from which it differs by 28561/28560.