770edo

Revision as of 12:11, 2 November 2023 by FloraC (talk | contribs) (Adopt template: Factorization; misc. cleanup)
← 769edo 770edo 771edo →
Prime factorization 2 × 5 × 7 × 11
Step size 1.55844 ¢ 
Fifth 450\770 (701.299 ¢) (→ 45\77)
Semitones (A1:m2) 70:60 (109.1 ¢ : 93.51 ¢)
Dual sharp fifth 451\770 (702.857 ¢) (→ 41\70)
Dual flat fifth 450\770 (701.299 ¢) (→ 45\77)
Dual major 2nd 131\770 (204.156 ¢)
Consistency limit 3
Distinct consistency limit 3

Template:EDO intro

Theory

770edo is inconsistent to the 5-odd-limit and harmonic 3 is about halfway between its steps. It has a reasonable approximation of the 2.9.5.7.11 subgroup, where it notably tempers out 9801/9800.

Odd harmonics

Approximation of odd harmonics in 770edo
Harmonic 3 5 7 9 11 13 15 17 19 21 23
Error Absolute (¢) -0.656 +0.180 +0.525 +0.246 +0.370 -0.528 -0.477 -0.540 +0.149 -0.132 -0.222
Relative (%) -42.1 +11.5 +33.7 +15.8 +23.8 -33.9 -30.6 -34.6 +9.6 -8.4 -14.3
Steps
(reduced)
1220
(450)
1788
(248)
2162
(622)
2441
(131)
2664
(354)
2849
(539)
3008
(698)
3147
(67)
3271
(191)
3382
(302)
3483
(403)

Subsets and supersets

Since 770 factors into 2 × 5 × 7 × 11, 770edo has subset edos 2, 5, 7, 10, 11, 14, 22, 35, 55, 70, 77, 110, 154, and 385. 1540edo, which doubles it, gives a good correction to the harmonic 3.

Regular temperament properties

Subgroup Comma List Mapping Optimal
8ve Stretch (¢)
Tuning Error
Absolute (¢) Relative (%)
2.9 [2441 -770 [770 2441]] -0.0388 0.0388 2.49
2.9.5 [61 2 -29, [40 -28 21 [770 2441 1788]] -0.0517 0.0365 2.34
2.9.5.7 43046721/43025920, 134217728/133984375, 1220703125/1219784832 [770 2441 1788 2162]] -0.0855 0.0666 4.27
2.9.5.7.11 9801/9800, 820125/819896, 1296000/1294139, 1362944/1361367 [770 2441 1788 2162 2664]] -0.0898 0.0602 3.86

Scales