76edo

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← 75edo 76edo 77edo →
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 15.8 ¢ each. Each step represents a frequency ratio of 21/76, or the 76th root of 2.

Theory

76edo's patent val is contorted in the 5-limit, reflecting the fact that 76 = 4 × 19. In the 7-limit it tempers out 2401/2400 in addition to 81/80, and so supports the squares temperament. In the 11-limit, it tempers out 245/242 and 385/384, and supports pombe, 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's 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 the 76dgh val, 76edo provides an excellent tuning for teff temperament, a low-complexity, medium-accuracy, and high-limit (17- or 19-limit) temperament.

Odd harmonics

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 (%) -45.7 -46.7 -35.9 +8.6 +8.3 -23.3 +7.6 +35.3 +15.8 +18.4 +20.9
Steps
(reduced)
120
(44)
176
(24)
213
(61)
241
(13)
263
(35)
281
(53)
297
(69)
311
(7)
323
(19)
334
(30)
344
(40)

Subsets and supersets

Since 76 factors into 22 × 19, 76edo has subset edos 2, 4, 19, and 38. 152edo, which doubles it, is a zeta peak edo.

Intervals

Steps Cents Approximate ratios Ups and downs notation
(Dual flat fifth 44\76)
Ups and downs notation
(Dual sharp fifth 45\76)
0 0 1/1 D D
1 15.8 ^D, ^E♭♭♭ ^D, vvE♭
2 31.6 ^^D, vvE♭♭ ^^D, vE♭
3 47.4 36/35, 38/37 vD♯, vE♭♭ ^3D, E♭
4 63.2 29/28 D♯, E♭♭ ^4D, ^E♭
5 78.9 23/22 ^D♯, ^E♭♭ ^5D, ^^E♭
6 94.7 ^^D♯, vvE♭ v5D♯, ^3E♭
7 110.5 vD𝄪, vE♭ v4D♯, ^4E♭
8 126.3 14/13 D𝄪, E♭ v3D♯, ^5E♭
9 142.1 ^D𝄪, ^E♭ vvD♯, v5E
10 157.9 34/31 ^^D𝄪, vvE vD♯, v4E
11 173.7 32/29 vD♯𝄪, vE D♯, v3E
12 189.5 19/17, 29/26, 39/35 E ^D♯, vvE
13 205.3 ^E, ^F♭♭ ^^D♯, vE
14 221.1 33/29 ^^E, vvF♭ E
15 236.8 vE♯, vF♭ ^E, vvF
16 252.6 22/19, 37/32 E♯, F♭ ^^E, vF
17 268.4 7/6 ^E♯, ^F♭ F
18 284.2 33/28 ^^E♯, vvF ^F, vvG♭
19 300 19/16, 25/21 vE𝄪, vF ^^F, vG♭
20 315.8 6/5 F ^3F, G♭
21 331.6 23/19 ^F, ^G♭♭♭ ^4F, ^G♭
22 347.4 ^^F, vvG♭♭ ^5F, ^^G♭
23 363.2 vF♯, vG♭♭ v5F♯, ^3G♭
24 378.9 F♯, G♭♭ v4F♯, ^4G♭
25 394.7 ^F♯, ^G♭♭ v3F♯, ^5G♭
26 410.5 33/26 ^^F♯, vvG♭ vvF♯, v5G
27 426.3 vF𝄪, vG♭ vF♯, v4G
28 442.1 F𝄪, G♭ F♯, v3G
29 457.9 ^F𝄪, ^G♭ ^F♯, vvG
30 473.7 ^^F𝄪, vvG ^^F♯, vG
31 489.5 vF♯𝄪, vG G
32 505.3 G ^G, vvA♭
33 521.1 23/17 ^G, ^A♭♭♭ ^^G, vA♭
34 536.8 ^^G, vvA♭♭ ^3G, A♭
35 552.6 11/8 vG♯, vA♭♭ ^4G, ^A♭
36 568.4 25/18, 32/23 G♯, A♭♭ ^5G, ^^A♭
37 584.2 7/5 ^G♯, ^A♭♭ v5G♯, ^3A♭
38 600 ^^G♯, vvA♭ v4G♯, ^4A♭
39 615.8 10/7 vG𝄪, vA♭ v3G♯, ^5A♭
40 631.6 23/16, 36/25 G𝄪, A♭ vvG♯, v5A
41 647.4 16/11 ^G𝄪, ^A♭ vG♯, v4A
42 663.2 ^^G𝄪, vvA G♯, v3A
43 678.9 34/23 vG♯𝄪, vA ^G♯, vvA
44 694.7 A ^^G♯, vA
45 710.5 ^A, ^B♭♭♭ A
46 726.3 ^^A, vvB♭♭ ^A, vvB♭
47 742.1 vA♯, vB♭♭ ^^A, vB♭
48 757.9 A♯, B♭♭ ^3A, B♭
49 773.7 ^A♯, ^B♭♭ ^4A, ^B♭
50 789.5 ^^A♯, vvB♭ ^5A, ^^B♭
51 805.3 vA𝄪, vB♭ v5A♯, ^3B♭
52 821.1 37/23 A𝄪, B♭ v4A♯, ^4B♭
53 836.8 ^A𝄪, ^B♭ v3A♯, ^5B♭
54 852.6 ^^A𝄪, vvB vvA♯, v5B
55 868.4 33/20, 38/23 vA♯𝄪, vB vA♯, v4B
56 884.2 5/3 B A♯, v3B
57 900 32/19, 37/22 ^B, ^C♭♭ ^A♯, vvB
58 915.8 ^^B, vvC♭ ^^A♯, vB
59 931.6 12/7 vB♯, vC♭ B
60 947.4 19/11 B♯, C♭ ^B, vvC
61 963.2 ^B♯, ^C♭ ^^B, vC
62 978.9 ^^B♯, vvC C
63 994.7 vB𝄪, vC ^C, vvD♭
64 1010.5 34/19 C ^^C, vD♭
65 1026.3 29/16 ^C, ^D♭♭♭ ^3C, D♭
66 1042.1 31/17 ^^C, vvD♭♭ ^4C, ^D♭
67 1057.9 vC♯, vD♭♭ ^5C, ^^D♭
68 1073.7 13/7 C♯, D♭♭ v5C♯, ^3D♭
69 1089.5 ^C♯, ^D♭♭ v4C♯, ^4D♭
70 1105.3 ^^C♯, vvD♭ v3C♯, ^5D♭
71 1121.1 vC𝄪, vD♭ vvC♯, v5D
72 1136.8 C𝄪, D♭ vC♯, v4D
73 1152.6 35/18, 37/19 ^C𝄪, ^D♭ C♯, v3D
74 1168.4 ^^C𝄪, vvD ^C♯, vvD
75 1184.2 vC♯𝄪, vD ^^C♯, vD
76 1200 2/1 D D

Notation

Ups and downs notation

Using Helmholtz–Ellis accidentals, 76edo can also be notated using ups and downs notation along with Stein–Zimmerman quarter-tone accidentals:

Step offset 0 1 2 3 4 5 6 7 8 9
Sharp symbol
Heji18.svg
Heji19.svg
HeQu1.svg
Heji24.svg
Heji25.svg
Heji26.svg
HeQu3.svg
Heji31.svg
Heji32.svg
Heji33.svg
Flat symbol
Heji17.svg
HeQd1.svg
Heji12.svg
Heji11.svg
Heji10.svg
HeQd3.svg
Heji5.svg
Heji4.svg
Heji3.svg

Here, a sharp raises by four steps, and a flat lowers by four steps, so arrows can be used to fill in the gap.

Sagittal notation

This notation uses the same sagittal sequence as EDOs 62 and 69, and is a superset of the notations for EDOs 38 and 19.

Evo flavor

76-EDO Evo Sagittal.svgSagittal notationPeriodic table of EDOs with sagittal notation1053/1024567/550

Revo flavor

76-EDO Revo Sagittal.svgSagittal notationPeriodic table of EDOs with sagittal notation1053/1024567/550

Evo-SZ flavor

76-EDO Evo-SZ Sagittal.svgSagittal notationPeriodic table of EDOs with sagittal notation1053/1024567/550

In the diagrams above, a sagittal symbol followed by an equals sign (=) means that the following comma is the symbol's primary comma (the comma it exactly represents in JI), while an approximately equals sign (≈) means it is a secondary comma (a comma it approximately represents in JI). In both cases the symbol exactly represents the tempered version of the comma in this EDO.

Instruments

Fretted instruments