11-odd-limit

Revision as of 19:55, 5 August 2026 by DesertFreeze (talk | contribs) (Moved Partch info to bottom)

The 11-odd-limit is the set of all rational intervals which can be written as 2k(a/b) where a, b ≤ 11 and k is an integer. To the 9-odd-limit, it adds 5 pairs of octave-reduced intervals involving 11.

Below is a list of all octave-reduced intervals in the 11-odd-limit.

Ratio Size (¢) Color name Name
12/11 150.637 1u2 lu 2nd lesser undecimal neutral second
11/10 165.004 1og2 logu 2nd greater undecimal neutral second
11/9 347.408 1o3 ilo 3rd undecimal neutral third
14/11 417.508 1uz4 luzo 4th undecimal major third
11/8 551.318 1o4 ilo 4th undecimal superfourth
16/11 648.682 1u5 lu 5th undecimal subfifth
11/7 782.492 1or5 loru 5th undecimal minor sixth
18/11 852.592 1u6 lu 6th undecimal neutral sixth
20/11 1034.996 1uy7 luyo 7th lesser undecimal neutral seventh
11/6 1049.363 1o7 ilo 7th greater undecimal neutral seventh

The smallest equal division of the octave which is consistent in the 11-odd-limit is 22edo.

The one which is distinctly consistent in the same is 58edo (also the smallest EDO to be consistent in the 17-odd-limit).

Link to Harry Partch

The 11-odd-limit is significant to Harry Partch's instruments and scales, with his 43-tone scale unequally dividing the octave into every 11-odd-limit ratio. He theorized about a tonality diamond that would support this scale, and built his diamond marimba (along with many other instruments) around this concept. He was, importantly, one of the pioneers of this concept.

See also