875/648

875/648, the maviloid generator superfourth, is a 7-limit just intonation interval measuring about 519.947 cents.

Theory

It can be used as the chroma-positive generator of the 99 & 373 temperament called maviloid, alongside with its octave inverse 1296/875, which is the chroma-negative generator. If used to make 2L 5s, It produces a very soft MOS with a step ratio of about 1.2.

It can be obtained by stacking three 5/4s and 81/56. It is higher than the perfect fourth 4/3 by 875/864, the keema, and thus the two are equated in the keemic family of temperaments.