11/6

11/6 |-1 -1 0 0 1>

1049.3629 cents

sound sample

11/6 is the undecimal neutral seventh of about 1049.4 cents. It can be treated as a consonance in 11-limit harmony, forming a part of such chords as 6:7:9:11 (1-7/6-3/2-11/6) and the neutral tetrad 18:22:27:33 (1-11/9-3/2-11/6).

Coincidentally, the ratio between the most common musical tuning frequency (A440) and the most common electrical AC frequency (60hz) is an 11/6, but two octaves up.