11/8

Interval information

Ratio	11/8
Factorization	2-3 × 11
Monzo	[-3 0 0 0 1⟩
Size in cents	551.3179¢
Name	undecimal superfourth
Color name	1o4, ilo 4th
FJS name	[math]\displaystyle{ \text{P4}^{11} }[/math]
Special properties	reduced, reduced harmonic
Tenney norm (log2 nd)	6.45943
Weil norm (log2 max(n, d))	6.91886
Wilson norm (sopfr(nd))	17
[sound info]
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In 11-limit Just Intonation, 11/8 is an undecimal (11-based) superfourth of about 551.3¢. Falling about halfway between 12edo's perfect fourth and tritone, it is very xenharmonic. It is the simplest superfourth in JI. As an octave-reduced overtone, it is a basis of consonance in 11-limit JI, alongside the lower odd numbers 9, 7, 5 and 3. It can be found in harmonic series chords such as 4:5:6:7:8:9:10:11:12, sitting somewhere between the much stronger and more familiar consonances of 10 (5) and 12 (3). It is very well-represented in 24edo, making that system especially good for approximations of JI chords involving primes 3 and 11 such as 8:9:11:12.

See also Gallery of Just Intervals