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ED8/5 is division of the just minor sixth (8/5) into n parts.

Division of 8/5 into equal parts can be conceived of as to directly use this interval as an equivalence, or not. The question of equivalence is still in its infancy. The utility of 8/5 (or another minor sixth) as a base though, is apparent by appearing in the famous "Neapolitan" sixth triad in common-practice tonal harmony and factoring into chord inversions. Many, if not all, of these scales have a perceptually important pseudo (false) octave, with various degrees of accuracy.

Incidentally, one way to treat 8/5 as an equivalence is the use of the classic minor triad 10:12:15:(16) (equated to the cluster 15:16:18):as the fundamental complete sonority in a very similar way to the classic major triad 4:5:6:(8) in meantone. Whereas in meantone it takes 4 3/2 to get 5/4, here it takes 4 3/2 to get to 6/5, which creates a rank-2 temperament tempering out the comma 16875/16384. This temperament yields MOS scales of the families 1L 4s<8/5>, 1L 5s<8/5>, 6L 1s<8/5>, 6L 7s<8/5>, and 6L 13s<8/5>. However, this temperament can sometimes result in pseudo-octaves particularly in near-CTE tuning range. As with other faster-than-octave-repeating temperament, this temperament is necessary to compromise by notating it like 64/25 (a diminished eleventh).