7980edo

From Xenharmonic Wiki
Jump to navigation Jump to search
← 7979edo 7980edo 7981edo →
Prime factorization 22 × 3 × 5 × 7 × 19
Step size 0.150376 ¢ 
Fifth 4668\7980 (701.955 ¢) (→ 389\665)
Semitones (A1:m2) 756:600 (113.7 ¢ : 90.23 ¢)
Consistency limit 9
Distinct consistency limit 9

7980 equal divisions of the octave (abbreviated 7980edo or 7980ed2), also called 7980-tone equal temperament (7980tet) or 7980 equal temperament (7980et) when viewed under a regular temperament perspective, is the tuning system that divides the octave into 7980 equal parts of about 0.15 ¢ each. Each step represents a frequency ratio of 21/7980, or the 7980th root of 2.

Theory

It is a very strong 5-limit system, tempering out Kirnberger's atom ([161 -84 -12) and the satanic comma ([1054 665), as well as [73 77 -84 and [234 -7 -96.

In the 7-limit, it tempers out the euzenius comma (78125000/78121827), the akjaysma (140737488355328/140710042265625), and [-17 50 1 -23.

In the 11-limit, using the patent val, it tempers out the kalisma (9801/9800), 47265625/47258883, 39630026842637/39627113103360, and 163470238547968/163443018796875.

Todo: review

Are the 7-limit and 11-limit descriptions musically relevant?

Approximation of prime harmonics in 7980edo
Harmonic 2 3 5 7 11 13 17 19 23 29 31
Error Absolute (¢) +0.0000 -0.0001 +0.0021 +0.0463 -0.0397 +0.0738 +0.0070 -0.0694 -0.0037 +0.0469 -0.0732
Relative (%) +0.0 -0.1 +1.4 +30.8 -26.4 +49.1 +4.7 -46.2 -2.4 +31.2 -48.7
Steps
(reduced)
7980
(0)
12648
(4668)
18529
(2569)
22403
(6443)
27606
(3666)
29530
(5590)
32618
(698)
33898
(1978)
36098
(4178)
38767
(6847)
39534
(7614)