144edo

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← 143edo144edo145edo →
Prime factorization 24 × 32
Step size 8.33333¢ 
Fifth 84\144 (700¢) (→7\12)
Semitones (A1:m2) 12:12 (100¢ : 100¢)
Consistency limit 11
Distinct consistency limit 11

144 equal divisions of the octave (abbreviated 144edo or 144ed2), also called 144-tone equal temperament (144tet) or 144 equal temperament (144et) when viewed under a regular temperament perspective, is the tuning system that divides the octave into 144 equal parts of about 8.33 ¢ each. Each step represents a frequency ratio of 21/144, or the 144th root of 2.

144edo's step size is called a farab when used as an interval size unit.[1]

Theory

144edo is closely related to 72edo, but the patent vals differ on the mapping for 13 and 17. It is enfactored in the 11-limit, tempering out 225/224, 243/242, 385/384, 441/440, and 4000/3993. Using the patent val, it tempers out 847/845, 1188/1183, 1701/1690, 1875/1859, and 4225/4224 in the 13-limit. It supports hemisecordite, the 41 & 103 temperament, though 103edo is better suited for this purpose.

Although the patent val comes out on top accuracy in the 13-limit, in the 17-limit 144 falls behind to 144g. The 144g val tempers out 170/169, 289/288, 375/374, 561/560, 595/594. It supports semihemisecordite, the 62 & 82f temperament. The patent val tempers out 273/272, 715/714, 833/832, 875/867, 891/884, and 1275/1274, supporting 17-limit hemisecordite. In the 19-limit the patent val tempers out 210/209, 325/323, 343/342, 363/361, 400/399, 513/512, and 665/663.

Besides all these, the 144eff val supports hemimiracle, the 41 & 103e temperament. 144ee supports oracle, the 31 & 113e temperament. 144cf supports necromanteion, the 31 & 113cf temperament.

Prime harmonics

Approximation of odd harmonics in 144edo
Harmonic 3 5 7 9 11 13 15 17 19 21 23
Error Absolute (¢) -1.96 -2.98 -2.16 -3.91 -1.32 +1.14 +3.40 +3.38 +2.49 -4.11 -3.27
Relative (%) -23.5 -35.8 -25.9 -46.9 -15.8 +13.7 +40.8 +40.5 +29.8 -49.4 -39.3
Steps
(reduced)
228
(84)
334
(46)
404
(116)
456
(24)
498
(66)
533
(101)
563
(131)
589
(13)
612
(36)
632
(56)
651
(75)

Subsets and supersets

144edo is the square of world-dominant 12edo.

Since 144 factors into 24 × 32, 144edo has subset edos 2, 3, 4, 6, 8, 9, 12, 16, 18, 24, 36, 48, and 72.

Approximation to φ

144edo is the 12th Fibonacci edo. As a consequence of being a Fibonacci edo, it can produce extremely precise approximation of the logarithmic golden ratio at 89 steps. Coincidentally, it also excellently represents the acoustic golden ratio by 100 steps.

Regular temperament properties

Subgroup Comma List Mapping Optimal
8ve Stretch (¢)
Tuning Error
Absolute (¢) Relative (%)
2.3.5.7.11.13 225/224, 243/242, 385/384, 847/845, 1875/1859 [144 228 334 404 498 533]] +0.560 0.595 7.13
2.3.5.7.11.13.17 170/169, 225/224, 243/242, 289/288, 375/374, 385/384 [144 228 334 404 498 533 588]] (144g) +0.653 0.596 7.15
2.3.5.7.11.13.17 225/224, 243/242, 273/272, 325/324, 847/845, 875/867 [144 228 334 404 498 533 589]] (144) +0.362 0.734 8.80

Rank-2 temperaments

Table of rank-2 temperaments by generator
Periods
per 8ve
Generator* Cents* Associated
Ratio*
Temperament
1 7\144 58.33 27/26 Hemisecordite (144)
2 7\144 58.33 27/26 Semihemisecordite (144g)
12 1\144 8.33 129/128 Dotcom

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

Music

Hideya

References

External links