369edo

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The 369 equal divisions of the octave (369edo), or the 369(-tone) equal temperament (369tet, 369et) when viewed from a regular temperament perspective, divides the octave into 369 equal parts of about 3.25 cents each.

← 368edo 369edo 370edo →
Prime factorization 32 × 41
Step size 3.25203 ¢ 
Fifth 216\369 (702.439 ¢) (→ 24\41)
Semitones (A1:m2) 36:27 (117.1 ¢ : 87.8 ¢)
Consistency limit 11
Distinct consistency limit 11

Theory

369 = 9 × 41, and it shares the fifth with 41edo. It has a sharp tendency, with harmonics 3 through 11 all tuned sharp. It tempers out 2401/2400 and 4375/4374 in the 7-limit, so that it supports the ennealimmal temperament; in the 11-limit, 4000/3993, 5632/5625 and 16384/16335. It provides the optimal patent val for the 11-limit 130&239 temperament, the 65&152 temperament, and the rank-4 temperament tempering out 16384/16335, the semiporwellisma, as well as the no-7 subgroup version of it.

Extension to the 13-limit is viable by the 369f val, tempering out 1575/1573, 2080/2079, 2200/2197, and 3584/3575. The optimal tuning of this temperament is consistent in the 15-integer-limit.

369 has subset edos 3, 9, 41, and 123.

Prime harmonics

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Regular temperament properties

Subgroup Comma list Mapping Optimal
8ve stretch (¢)
Tuning error
Absolute (¢) Relative (%)
2.3.5 [32 -7 -9, [1 -27 18 [369 585 857]] -0.1991 0.1409 4.33
2.3.5.7 2401/2400, 4375/4374, [32 -7 -9 [369 585 857 1036]] -0.1743 0.1294 3.98
2.3.5.7.11 2401/2400, 4000/3993, 4375/4374, 5632/5625 [369 585 857 1036 1277]] -0.2277 0.1576 4.85
2.3.5.7.11.13 1575/1573, 2080/2079, 2200/2197, 2401/2400, 3584/3575 [369 585 857 1036 1277 1366]] (369f) -0.2685 0.1703 5.24

Rank-2 temperaments

Table of rank-2 temperaments by generator
Periods
per octave
Generator
(reduced)
Cents
(reduced)
Associated
ratio
Temperaments
1 17\369 55.28 33/32 Escapade
1 172\369 559.35 864/625 Tritriple (5-limit)
9 77\369
(5\369)
250.41
(16.26)
140/121
(100/99)
Semiennealimmal
9 97\369
(15\369)
315.45
(48.78)
6/5
(36/35)
Ennealimmal
9 68\369
(14\369)
221.14
(45.53)
25/22
(77/75)
Quadraennealimmal
41 55\369
(1\369)
178.86
(3.25)
567/512
(352/351)
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