729/640

Interval information

Ratio	729/640
Factorization	2-7 × 36 × 5-1
Monzo	[-7 6 -1⟩
Size in cents	225.4163¢
Name	acute whole tone
Color name	Lg2, lagu 2nd
FJS name	[math]\displaystyle{ \text{M2}_{5} }[/math]
Special properties	reduced
Tenney norm (log2 nd)	18.8317
Weil norm (log2 max(n, d))	19.0196
Wilson norm (sopfr(nd))	37
Open this interval in xen-calc

729/640 is the interval that results from stacking 16/15 (classical diatonic semitone) and 2187/2048 (Pythagorean apotome), or 27/25 (large limma) and 135/128 (major limma). It is equal to 9/8 raised by a syntonic comma, about 225.4 cents in size, and well approximated by three steps of 16edo, and 16 of them exceed three octaves by the comma (729/640)¹⁶/2³ = 3⁹⁶/(2¹¹⁵×5¹⁶) = [-115 96 -16⟩ (lela-quadquadgu negative 6th, ~6.66 cents).

See also

• 1280/729 – its octave complement
• Gallery of just intervals