108edo
Theory
108edo tempers out the Pythagorean comma, 531441/524288, in the 3-limit and 1990656/1953125, the valensixthtone comma, in the 5-limit. In the 7-limit it tempers out 126/125 and 1029/1024, supporting valentine temperament, and making for a good tuning for it and for starling temperament, the planar temperament tempering out 126/125. In the 11-limit the patent val tempers out 540/539 and the 108e val tempers out 121/120 and 176/175, supporting 11-limit valentine for which it is again a good tuning.
108edo is the smallest 12n-edo which offers a decent alternative fifth to 12edo's fifth, that is 27edo's superpyth fifth.
Prime harmonics
| Harmonic | 2 | 3 | 5 | 7 | 11 | 13 | 17 | 19 | 23 | 29 | 31 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Error | Absolute (¢) | +0.00 | -1.96 | +2.58 | -2.16 | +4.24 | +3.92 | -4.96 | +2.49 | +5.06 | +3.76 | -0.59 |
| Relative (%) | +0.0 | -17.6 | +23.2 | -19.4 | +38.1 | +35.3 | -44.6 | +22.4 | +45.5 | +33.8 | -5.3 | |
| Steps (reduced) |
108 (0) |
171 (63) |
251 (35) |
303 (87) |
374 (50) |
400 (76) |
441 (9) |
459 (27) |
489 (57) |
525 (93) |
535 (103) | |