460edo

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The 460 equal divisions of the octave divides the octave into 460 equal parts of 2.609 cents each.

460edo is a very strong 19-limit system and is uniquely consistent to the 21-odd-limit, with harmonics of 3 to 19 all tuned flat. It tempers out the schisma, 32805/32768, in the 5-limit and 4375/4374 and 65536/65625 in the 7-limit, so that it supports pontiac. In the 11-limit it tempers of 43923/43904, 3025/3024 and 9801/9800; in the 13-limit 1001/1000, 4225/4224 and 10648/10647; in the 17-limit 833/832, 1089/1088, 1225/1224, 1701/1700, 2058/2057, 2431/2430, 2601/2600 and 4914/4913; and in the 19-limit 1331/1330, 1445/1444, 1521/1520, 1540/1539, 1729/1728, 2376/2375, 2926/2925, 3136/3135, 3250/3249 and 4200/4199. It serves as the optimal patent val for various temperaments such as the rank five temperament tempering out 833/832 and 1001/1000.

Prime harmonics

Approximation of prime harmonics in 460edo
Harmonic 2 3 5 7 11 13 17 19 23 29 31
Error Absolute (¢) +0.00 -0.22 -0.23 -1.00 -0.88 -0.53 -0.61 -0.12 +0.42 +0.86 +0.18
Relative (%) +0.0 -8.3 -8.7 -38.3 -33.9 -20.2 -23.3 -4.7 +16.2 +32.9 +7.0
Steps
(reduced)
460
(0)
729
(269)
1068
(148)
1291
(371)
1591
(211)
1702
(322)
1880
(40)
1954
(114)
2081
(241)
2235
(395)
2279
(439)

Regular temperament properties

Subgroup Comma list Mapping Optimal
8ve stretch (¢)
Tuning error
Absolute (¢) Relative (%)
2.3 [-729 460 [460 729]] +0.0681 0.0681 2.61
2.3.5 32805/32768, [6 68 -49 [460 729 1068]] +0.0780 0.0573 2.20
2.3.5.7 4375/4374, 32805/32768, [-4 -2 -9 10 [460 729 1068 1291]] +0.1475 0.1303 4.99
2.3.5.7.11 3025/3024, 4375/4374, 32805/32768, 184877/184320 [460 729 1068 1291 1591]] +0.1691 0.1243 4.76
2.3.5.7.11.13 1001/1000, 3025/3024, 4225/4224, 4375/4374, 26411/26364 [460 729 1068 1291 1591 1702]] +0.1647 0.1139 4.36
2.3.5.7.11.13.17 833/832, 1001/1000, 1089/1088, 1225/1224, 1701/1700, 4225/4224 [460 729 1068 1291 1591 1702 1880]] +0.1624 0.1056 4.05
2.3.5.7.11.13.17.19 833/832, 1001/1000, 1089/1088, 1225/1224, 1331/1330, 1445/1444, 1617/1615 [460 729 1068 1291 1591 1702 1880 1954]] +0.1457 0.1082 4.15

Rank-2 temperaments

Table of rank-2 temperaments by generator
Periods
per octave
Generator
(reduced)
Cents
(reduced)
Associated
ratio
Temperaments
1 121\460 315.65 6/5 Egads
1 191\460 498.26 4/3 Helmholtz / pontiac
10 121\460
(17\460)
315.65
(44.35)
6/5
(40/39)
Deca