# 103edo

 ← 102edo 103edo 104edo →
Prime factorization 103 (prime)
Step size 11.6505¢
Fifth 60\103 (699.029¢)
Semitones (A1:m2) 8:9 (93.2¢ : 104.9¢)
Consistency limit 7
Distinct consistency limit 7

103 equal divisions of the octave (abbreviated 103edo or 103ed2), also called 103-tone equal temperament (103tet) or 103 equal temperament (103et) when viewed under a regular temperament perspective, is the tuning system that divides the octave into 103 equal parts of about 11.7 ¢ each. Each step represents a frequency ratio of 21/103, or the 103rd root of 2.

## Theory

In 103edo, all intervals within the 17-odd-limit are consistent, with the sole exception of 9/8 and its octave complement 16/9, which barely miss (relative error 50.2%). Its closest zeta peak index, 596zpi, stretches the octave by +0.739 cents. This expansion is uniquely consistent within the 15-integer-limit.

103edo is a good miracle tuning, especially for the 7-limit, and for benediction and hemisecordite, two of the 13-limit extensions of miracle. It tempers out 78732/78125 in the 5-limit; 225/224, 1029/1024 and 2401/2400 in the 7-limit; 243/242, 441/440 and 540/539 in the 11-limit; 351/350 and 847/845 in the 13-limit. In the 13-limit it provides the optimal patent val for marvel temperament as well as benediction and hemisecordite.

### Prime harmonics

Approximation of prime harmonics in 103edo
Harmonic 2 3 5 7 11 13 17 19 23 29 31
Error Absolute (¢) +0.00 -2.93 -1.85 -1.84 -3.75 -1.69 -0.10 +5.40 +0.85 -4.33 -3.29
Relative (%) +0.0 -25.1 -15.9 -15.8 -32.1 -14.5 -0.9 +46.3 +7.3 -37.2 -28.2
Steps
(reduced)
103
(0)
163
(60)
239
(33)
289
(83)
356
(47)
381
(72)
421
(9)
438
(26)
466
(54)
500
(88)
510
(98)

### Subsets and supersets

103edo is the 27th prime edo, following 101edo and before 107edo.

## Regular temperament properties

Subgroup Comma List Mapping Optimal
8ve Stretch (¢)
Tuning Error
Absolute (¢) Relative (%)
2.3 [-163 103 [103 166]] +0.923 0.924 7.92
2.3.5 78732/78125, 34171875/33554432 [103 166 239]] +0.881 0.757 6.49
2.3.5.7 225/224, 1029/1024, 78732/78125 [103 166 239 289]] +0.824 0.663 5.68
2.3.5.7.11 225/224, 243/242, 385/384, 43923/43750 [103 166 239 289 356]] +0.876 0.602 5.16
2.3.5.7.11.13 225/224, 243/242, 351/350, 385/384, 847/845 [103 166 239 289 356 381]] +0.806 0.571 4.90
2.3.5.7.11.13.17 225/224, 243/242, 273/272, 351/350, 375/374, 847/845 [103 166 239 289 356 381 421]] +0.694 0.595 5.10

### Rank-2 temperaments

Table of rank-2 temperaments by generator
Periods
per 8ve
Generator* Cents* Associated
Ratio*
Temperaments
1 3\103 34.951 1990656/1953125 Gammy
1 5\103 58.252 27/26 Hemisecordite
1 9\103 104.854 17/16 Septendesemi
1 10\103 116.505 15/14~16/15 Miracle / benediction
1 16\103 186.408 10/9 Mintone
1 20\103 233.010 8/7 Slendric
1 21\103 244.660 15/13 Subsemifourth
1 26\103 303.013 25/21 Quinmite
1 31\103 361.165 16/13 Phicordial
1 37\103 431.06 77/60 Lockerbie
1 38\103 442.708 162/125 Sensei
1 39\103 454.369 13/10 Fibo
1 40\103 466.019 55/42 Hemiseptisix
1 42\103 489.320 65/49 Catafourth
1 45\103 524.272 65/48 Widefourth
1 47\103 547.573 11/8 Heinz
1 48\103 559.223 242/175 Tritriple
1 50\103 582.524 7/5 Neptune

* octave-reduced form, reduced to the first half-octave, and minimal form in parentheses if it is distinct

Francium