Sinbadmic chords

A sinbadmic chord is a 13-limit essentially tempered dyadic chord which is tempered by 1001/1000 (sinbadma).

The triads are of the form

• 1–7/5–20/13, with steps of 7/5, 11/10, 13/10,

and its inversion,

• 1–7/5–20/11, with steps of 7/5, 13/10, 11/10.

They can be extended to following palindromic tetrads:

• 1–11/10–13/10–10/7 with steps of 11/10, 13/11, 11/10, 7/5;
• 1–11/10–10/7–11/7 with steps of 11/10, 13/10, 11/10, 14/11;
• 1–13/10–10/7–13/7 with steps of 13/10, 11/10, 13/10, 14/13.

Equal temperaments with sinbadmic chords include 29, 31, 43, 50, 53, 58, 72, 87, 103, 111, 130, 183, 190, 198, 270, 571, 590, 643, 860, 1130, 1431 and 1701, with 1701edo giving the optimal patent val.

The name is derived from the sinbadma (1001/1000), a comma that is reminiscent of the tales of 1001 Nights.