140edo
← 139edo | 140edo | 141edo → |
140 equal divisions of the octave (abbreviated 140edo or 140ed2), also called 140-tone equal temperament (140tet) or 140 equal temperament (140et) when viewed under a regular temperament perspective, is the tuning system that divides the octave into 140 equal parts of about 8.57 ¢ each. Each step represents a frequency ratio of 21/140, or the 140th root of 2.
Theory
In the 5-limit, 140et tempers out 15625/15552, making it a kleismic system, and the kwazy comma, [-53 10 16⟩. It is most notable, however, in the 7-limit, where it tempers out 2401/2400, 5120/5103, 10976/10935 and 65625/65536. It supports the 7-limit rank-2 temperaments tertiaseptal, hemififths, countercata and bisupermajor, and is a good tuning recommendation for countercata, the 53 & 87 temperament tempering out 15625/15552 and 5120/5103, and provides the optimal patent val for 13-limit countercata. In the 11-limit it tempers out 385/384, 1331/1323, 1375/1372, 5632/5625, 6250/6237 and 9801/9800, and in the 13-limit 325/324, 352/351, 625/624, 676/675, 847/845, 1001/1000, 1716/1715 and 2080/2079.
If we use the val ⟨140 223 325 394] (140bbd) we obtain a tuning for porcupine temperament; the generator 19\140 is 0.023 cents flat of the POTE generator.
Prime harmonics
Harmonic | 2 | 3 | 5 | 7 | 11 | 13 | 17 | 19 | 23 | 29 | |
---|---|---|---|---|---|---|---|---|---|---|---|
Error | Absolute (¢) | +0.00 | +0.90 | -0.60 | -0.25 | -2.75 | -0.53 | -2.10 | +2.49 | -2.56 | -1.01 |
Relative (%) | +0.0 | +10.5 | -7.0 | -3.0 | -32.0 | -6.2 | -24.5 | +29.0 | -29.9 | -11.7 | |
Steps (reduced) |
140 (0) |
222 (82) |
325 (45) |
393 (113) |
484 (64) |
518 (98) |
572 (12) |
595 (35) |
633 (73) |
680 (120) |
Harmonic | 31 | 37 | 41 | 43 | 47 | 53 | 59 | 61 | 67 | 71 | |
---|---|---|---|---|---|---|---|---|---|---|---|
Error | Absolute (¢) | +3.54 | -2.77 | -0.49 | +2.77 | +3.06 | +0.78 | +3.69 | -2.60 | -2.16 | +0.30 |
Relative (%) | +41.3 | -32.3 | -5.7 | +32.3 | +35.8 | +9.1 | +43.0 | -30.3 | -25.2 | +3.5 | |
Steps (reduced) |
694 (134) |
729 (29) |
750 (50) |
760 (60) |
778 (78) |
802 (102) |
824 (124) |
830 (130) |
849 (9) |
861 (21) |
Subsets and supersets
Since 140 factors into 22 × 5 × 7, 140edo has subset edos 2, 4, 5, 7, 10, 14, 20, 28, 35, and 70.
Regular temperament properties
Subgroup | Comma List | Mapping | Optimal 8ve Stretch (¢) |
Tuning Error | |
---|---|---|---|---|---|
Absolute (¢) | Relative (%) | ||||
2.3.5 | 15625/15552, [35 -25 2⟩ | [⟨140 222 325]] | -0.104 | 0.346 | 4.03 |
2.3.5.7 | 2401/2400, 5120/5103, 15625/15552 | [⟨140 222 325 393]] | -0.055 | 0.311 | 3.63 |
2.3.5.7.11 | 385/384, 1331/1323, 1375/1372, 2200/2187 | [⟨140 222 325 393 484]] | +0.115 | 0.439 | 5.12 |
2.3.5.7.11.13 | 325/324, 352/351, 385/384, 625/624, 1331/1323 | [⟨140 222 325 393 484 518]] | +0.119 | 0.401 | 4.68 |
2.3.5.7.11.13.17 | 289/288, 325/324, 352/351, 385/384, 442/441, 625/624 | [⟨140 222 325 393 484 518 572]] | +0.176 | 0.396 | 4.62 |
- 140et has lower absolute errors than any previous equal temperaments in the 17-, 19-, and 23-limit, and perhaps beyond. In the 17-limit it is the first to beat 121 and is superseded by 171. In the 19- and 23-limit it is the first to beat 130 and is superseded by 152fg.
Rank-2 temperaments
Periods per 8ve |
Generator* | Cents* | Associated Ratio* |
Temperaments |
---|---|---|---|---|
1 | 9\140 | 77.14 | 22/21 | Tertiaseptal / tertia |
1 | 13\140 | 111.43 | 16/15 | Stockhausenic |
1 | 37\140 | 317.14 | 6/5 | Countercata |
1 | 41\140 | 351.43 | 49/40 | Hemififths |
1 | 53\140 | 454.29 | 13/10 | Fibo |
1 | 59\140 | 505.71 | 75/56 | Marfifths |
2 | 3\140 | 25.71 | 64/63 | Ketchup |
2 | 19\140 | 162.86 | 11/10 | Bisupermajor |
2 | 41\140 (29\140) |
351.43 (248.57) |
49/40 (15/13) |
Semihemi |
4 | 37\140 (2\140) |
317.14 (17.14) |
6/5 (126/125) |
Quadritikleismic |
4 | 58\140 (12\140) |
497.14 (102.86) |
4/3 (35/33) |
Undim |
5 | 43\140 (13\140) |
368.57 (111.43) |
1024/891 (16/15) |
Quintosec |
10 | 29\140 (1\140) |
248.57 (8.57) |
15/13 (176/175) |
Decoid |
20 | 54\140 (2\140) |
497.14 (17.14) |
4/3 (126/125) |
Degrees |
28 | 54\140 (2\140) |
497.14 (17.14) |
4/3 (126/125) |
Oquatonic |
* octave-reduced form, reduced to the first half-octave, and minimal form in parentheses if it is distinct