76edo

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← 75edo76edo77edo →
Prime factorization 22 × 19
Step size 15.7895¢
Fifth 44\76 (694.737¢) (→11\19)
Semitones (A1:m2) 4:8 (63.16¢ : 126.3¢)
Dual sharp fifth 45\76 (710.526¢)
Dual flat fifth 44\76 (694.737¢) (→11\19)
Dual major 2nd 13\76 (205.263¢)
Consistency limit 7
Distinct consistency limit 7

76 equal divisions of the octave (abbreviated 76edo or 76ed2), also called 76-tone equal temperament (76tet) or 76 equal temperament (76et) when viewed under a regular temperament perspective, is the tuning system that divides the octave into 76 equal parts of about 15.789 ¢ each. Each step represents a frequency ratio of 21/76, or the 76th root of 2.

Theory

Approximation of odd harmonics in 76edo
Harmonic 3 5 7 9 11 13 15 17 19 21 23
Error absolute (¢) -7.22 -7.37 -5.67 +1.35 +1.31 -3.69 +1.20 +5.57 +2.49 +2.90 +3.30
relative (%) -46 -47 -36 +9 +8 -23 +8 +35 +16 +18 +21
Steps
(reduced)
120
(44)
176
(24)
213
(61)
241
(13)
263
(35)
281
(53)
297
(69)
311
(7)
323
(19)
334
(30)
344
(40)

This tuning's 5-limit patent val is contorted in the 5-limit, reflecting the fact that 76 = 4 * 19. In the 7-limit it tempers out 2401/2400 as well as 81/80, and so supports squares temperament. In the 11-limit, it tempers out 245/242 and 385/384, and supports the 24&26 temperament. In the 13-limit, it tempers out 105/104, 144/143, 351/350 and 364/363. While the 44\76 = 11\19 fifth is already flat, the 43\76 fifth, even flatter, is an almost perfect approximation to the hornbostel temperament POTE fifth, whereas its sharp fifth, 45\76, makes for an excellent superpyth fifth. Hence you can do hornbostel/mavila, squares/meantone, and superpyth all with the same equal division.

Using non-patent vals, 76edo provides an excellent tuning for teff temperament, a low complexity, medium accuracy, and high limit (17 or 19) temperament.

Intervals

Steps Cents Ups and downs notation
(dual flat fifth 44\76)
Ups and downs notation
(dual sharp fifth 45\76)
Approximate ratios
0 0 D D 1/1
1 15.7895 ^D, v3Ebb ^D, vvEb
2 31.5789 ^^D, vvEbb ^^D, vEb 49/48, 50/49, 56/55, 66/65
3 47.3684 ^3D, vEbb ^3D, Eb 33/32, 36/35, 40/39
4 63.1579 D#, Ebb ^4D, v10E 80/77
5 78.9474 ^D#, v3Eb ^5D, v9E 21/20
6 94.7368 ^^D#, vvEb ^6D, v8E 55/52
7 110.526 ^3D#, vEb ^7D, v7E
8 126.316 Dx, Eb ^8D, v6E 14/13
9 142.105 ^Dx, v3E ^9D, v5E 13/12
10 157.895 ^^Dx, vvE ^10D, v4E
11 173.684 ^3Dx, vE D#, v3E 72/65
12 189.474 E ^D#, vvE 39/35
13 205.263 ^E, v3Fb ^^D#, vE 55/49
14 221.053 ^^E, vvFb E
15 236.842 ^3E, vFb ^E, vvF 8/7, 55/48
16 252.632 E#, Fb ^^E, vF 65/56
17 268.421 ^E#, v3F F 7/6, 64/55
18 284.211 ^^E#, vvF ^F, vvGb 13/11, 33/28
19 300 ^3E#, vF ^^F, vGb 25/21
20 315.789 F ^3F, Gb 6/5, 77/64
21 331.579 ^F, v3Gbb ^4F, v10G 40/33
22 347.368 ^^F, vvGbb ^5F, v9G 49/40, 60/49
23 363.158 ^3F, vGbb ^6F, v8G 16/13
24 378.947 F#, Gbb ^7F, v7G
25 394.737 ^F#, v3Gb ^8F, v6G 49/39, 63/50
26 410.526 ^^F#, vvGb ^9F, v5G 33/26
27 426.316 ^3F#, vGb ^10F, v4G 50/39
28 442.105 Fx, Gb F#, v3G
29 457.895 ^Fx, v3G ^F#, vvG 13/10
30 473.684 ^^Fx, vvG ^^F#, vG
31 489.474 ^3Fx, vG G 65/49
32 505.263 G ^G, vvAb
33 521.053 ^G, v3Abb ^^G, vAb 65/48, 66/49
34 536.842 ^^G, vvAbb ^3G, Ab 49/36
35 552.632 ^3G, vAbb ^4G, v10A 11/8, 48/35
36 568.421 G#, Abb ^5G, v9A 25/18, 39/28
37 584.211 ^G#, v3Ab ^6G, v8A 7/5
38 600 ^^G#, vvAb ^7G, v7A 55/39, 78/55
39 615.789 ^3G#, vAb ^8G, v6A 10/7
40 631.579 Gx, Ab ^9G, v5A 36/25, 56/39
41 647.368 ^Gx, v3A ^10G, v4A 16/11, 35/24
42 663.158 ^^Gx, vvA G#, v3A 72/49
43 678.947 ^3Gx, vA ^G#, vvA 49/33, 77/52
44 694.737 A ^^G#, vA
45 710.526 ^A, v3Bbb A
46 726.316 ^^A, vvBbb ^A, vvBb
47 742.105 ^3A, vBbb ^^A, vBb 20/13
48 757.895 A#, Bbb ^3A, Bb 65/42
49 773.684 ^A#, v3Bb ^4A, v10B 39/25
50 789.474 ^^A#, vvBb ^5A, v9B 52/33
51 805.263 ^3A#, vBb ^6A, v8B 78/49
52 821.053 Ax, Bb ^7A, v7B 77/48
53 836.842 ^Ax, v3B ^8A, v6B 13/8
54 852.632 ^^Ax, vvB ^9A, v5B 49/30, 80/49
55 868.421 ^3Ax, vB ^10A, v4B 33/20
56 884.211 B A#, v3B 5/3
57 900 ^B, v3Cb ^A#, vvB 42/25
58 915.789 ^^B, vvCb ^^A#, vB 22/13, 56/33
59 931.579 ^3B, vCb B 12/7, 55/32
60 947.368 B#, Cb ^B, vvC
61 963.158 ^B#, v3C ^^B, vC 7/4
62 978.947 ^^B#, vvC C
63 994.737 ^3B#, vC ^C, vvDb
64 1010.53 C ^^C, vDb 70/39
65 1026.32 ^C, v3Dbb ^3C, Db 65/36
66 1042.11 ^^C, vvDbb ^4C, v10D
67 1057.89 ^3C, vDbb ^5C, v9D 24/13
68 1073.68 C#, Dbb ^6C, v8D 13/7
69 1089.47 ^C#, v3Db ^7C, v7D
70 1105.26 ^^C#, vvDb ^8C, v6D
71 1121.05 ^3C#, vDb ^9C, v5D 40/21
72 1136.84 Cx, Db ^10C, v4D 77/40
73 1152.63 ^Cx, v3D C#, v3D 35/18, 39/20, 64/33
74 1168.42 ^^Cx, vvD ^C#, vvD 49/25, 55/28, 65/33
75 1184.21 ^3Cx, vD ^^C#, vD
76 1200 D D 2/1