20480/19683

Interval information
Ratio	20480/19683
Factorization	212 × 3-9 × 5
Monzo	[12 -9 1⟩
Size in cents	68.71871¢
Names	retroptolemaic minor second,; superpyth comma
Color name	sayo 2nd, sayo comma
FJS name	[math]\displaystyle{ \text{m2}^{5} }[/math]
Special properties	reduced
Tenney norm (log2 nd)	28.5866
Weil norm (log2 max(n, d))	28.6439
Wilson norm (sopfr(nd))	56
	Open this interval in xen-calc

20480/19683, the retroptolemaic minor second, is a 5-limit interval measuring about 68.7 ¢. It is equal to the Pythagorean minor second (256/243) flattened by a syntonic comma (81/80). When treated as a comma to be tempered out, it is the superpyth comma, and is the difference between 5/4 and an octave-reduced stack of nine 3/2's, as well as 25/24 minus a schisma (32805/32768). Tempering it out by itself defines the 5-limit version of superpyth temperament. Notable edos that temper it out include 17, 22, and 27.