11edo
From Xenharmonic Reference
11edo, or 11 equal divisions of the octave, is the equal tuning featuring steps of (1200/1) ~= 109.09 cents, 11 of which stack to the perfect octave 2/1. It does not approximate many small prime harmonics well at all. But approximates 11/8 exceptionally well for it's size and also approximates the interval 9/7 with only ~1 cent of error. It has 2 fifths at 654.55c and 763.64c.
