31edo

From Xenharmonic Wiki
(Redirected from 31-edo)
Jump to navigation Jump to search
← 30edo 31edo 32edo →
Prime factorization 31 (prime)
Step size 38.7097¢ 
Fifth 18\31 (696.774¢)
Semitones (A1:m2) 2:3 (77.42¢ : 116.1¢)
Consistency limit 11
Distinct consistency limit 7
Special properties

31 equal divisions of the octave (abbreviated 31edo or 31ed2), also called 31-tone equal temperament (31tet) or 31 equal temperament (31et) when viewed under a regular temperament perspective, is the tuning system that divides the octave into 31 equal parts of about 38.7 ¢ each. Each step represents a frequency ratio of 21/31, or the 31st root of 2.

31edo is also referred to as the tricesimoprimal meantone temperament. The term tricesimoprimal was first used by Adriaan Fokker.

English Wikipedia has an article on:

Theory

31edo's perfect fifth is flat of the just interval 3/2 (over five cents), as befits a tuning supporting meantone, but the major third is less than a cent sharp of just 5/4, making it slightly sharp of quarter-comma meantone. 31's approximation of 7/4, a cent flat, is also very close to just. It is a very tone-efficient melodic approximation of the 11-limit (and specifically the 11-odd-limit), although it conflates 9/7 with 14/11 and 11/8 with 15/11. Many 7-limit JI scales are well-approximated in 31 (with tempering, of course). It also maps all 15-odd-limit intervals consistently, with the sole exceptions of 13/9, 13/11, 18/13, and 22/13.

Because of the near-just 5/4 and 7/4 and because the 11th harmonic is almost twice as flat as the 3rd harmonic, 31edo is relatively quite accurate and is the 6th zeta integral edo, the 7th zeta gap edo, a zeta peak edo, and a zeta peak integer edo, meaning it is a strict zeta edo. Other ways in which 31edo is especially accurate is that it represents a record in Pepper ambiguity in the 7-, 9-, and 11-odd-limit, which it is consistent through, and that it is the first non-trivial edo to be consistent in the 11-odd-prime-sum-limit.

One step of 31edo, measuring about 38.7¢, is called a diesis because it stands in for several intervals called "dieses" (most notably, 128/125 and 648/625) which are tempered out in 12edo. The diesis is a defining sound of 31edo; when it does not appear directly in a scale, it often shows up as the difference between two or more intervals of a similar size. The diesis is demonstrated in SpiralProgressions. Zhea Erose's 31edo music uses the interval frequently.

31edo is close to a circle made by stacking 31 pure 17/13 subfourths. A circle of 31 pure 17/13's closes with an error of only 2.74 cents (relative error 7.1%). Remarkably, 31edo tempers out 83521/83486, the 0.7-cent difference between a stack of four 17/13's and a stack of one 19/13 and one 2/1, giving 31edo's oneirotonic (5L 3s) mos accurate 13:17:19 chords.

Prime harmonics

Approximation of prime harmonics in 31edo
Harmonic 2 3 5 7 11 13 17 19 23 29 31 37
Error Absolute (¢) +0.0 -5.2 +0.8 -1.1 -9.4 +11.1 +11.2 +12.2 -8.9 +15.6 +16.3 -19.1
Relative (%) +0.0 -13.4 +2.0 -2.8 -24.2 +28.6 +28.9 +31.4 -23.0 +40.3 +42.0 -49.3
Steps
(reduced)
31
(0)
49
(18)
72
(10)
87
(25)
107
(14)
115
(22)
127
(3)
132
(8)
140
(16)
151
(27)
154
(30)
161
(6)
Approximation of prime harmonics in 31edo (continued)
Harmonic 41 43 47 53 59 61 67 71 73 79 83 89
Error Absolute (¢) -3.3 -8.3 -7.4 +16.8 -14.0 +5.7 -1.9 +13.9 +4.5 -16.1 +14.5 +9.8
Relative (%) -8.4 -21.4 -19.2 +43.4 -36.2 +14.7 -4.9 +35.8 +11.5 -41.7 +37.4 +25.2
Steps
(reduced)
166
(11)
168
(13)
172
(17)
178
(23)
182
(27)
184
(29)
188
(2)
191
(5)
192
(6)
195
(9)
198
(12)
201
(15)

Subsets and supersets

31edo is the 11th prime edo, following 29edo and coming before 37edo.

Intervals

Degree Cents Approximate Ratios[note 1] Ups and downs notation
(EUs: vvA1 and vd2)
Extended pythagorean notation SKULO notation (S or U = 1)
0 0.00 1/1 P1 perfect unison D P1 perfect unison D P1 perfect unison D
1 38.71 45/44, 49/48, 46/45, 128/125, 36/35 ^1, d2 up-unison, dim 2nd ^D, Ebb d2 dim 2nd Ebb S1/U1 super/uber unison SD/UD
2 77.42 25/24, 21/20, 22/21, 23/22 A1, vm2 aug 1sn, downminor 2nd D#, vEb A1 aug 1sn D# sm2 subminor 2nd sEb
3 116.13 15/14, 16/15 m2 minor 2nd Eb m2 minor 2nd Eb m2 minor 2nd Eb
4 154.84 12/11, 11/10, 35/32 ~2 mid 2nd vE AA1, dd3 double-aug 1sn, double-dim 3rd Dx, Fbb N2 neutral 2nd UEb/uE
5 193.55 9/8, 10/9, 19/17, 28/25 M2 major 2nd E M2 major 2nd E M2 major 2nd E
6 232.26 8/7, 144/125 ^M2 upmajor 2nd ^E d3 dim 3rd Fb SM2 supermajor 2nd SE
7 270.97 7/6, 75/64 vm3 downminor 3rd vF A2 aug 2nd E# sm3 subminor 3rd sF
8 309.68 6/5, 25/21 m3 minor 3rd F m3 minor 3rd F m3 minor 3rd F
9 348.39 11/9, 27/22, 16/13, 60/49, 49/40 ~3 mid 3rd ^F AA2, dd4 double-aug 2nd, double-dim 4th Ex, Gbb N3 neutral 3rd UF/uF#
10 387.10 5/4 M3 major 3rd F# M3 major 3rd F# M3 major 3rd F#
11 425.81 9/7, 14/11, 23/18, 32/25 ^M3 upmajor 3rd ^F# d4 dim 4th Gb SM3 supermajor 3rd SF#
12 464.52 21/16, 64/49, 13/10, 17/13, 125/96 v4 down-4th vG A3 aug 3rd Fx s4 sub 4th sG
13 503.23 4/3 P4 perfect 4th G P4 perfect 4th G P4 perfect 4th G
14 541.94 175/128, 11/8, 15/11, 26/19 ^4, ~4 up-4th, mid 4th ^G AA3, dd5 double-aug 3rd, double-dim 5th Fx#, Abb U4/N4 uber/neutral 4th UG
15 580.65 7/5, 45/32, 25/18 A4, vd5 aug 4th, downdim 5th G#, vAb A4 aug 4th G# A4 aug 4th G#
16 619.35 10/7, 64/45, 36/25 ^A4, d5 upaug 4th, dim 5th ^G#, Ab d5 dim 5th Ab d5 dim 5th Ab
17 658.06 256/175, 16/11, 22/15, 19/13 v5, ~5 down-5th, mid 5th vA AA4, dd6 double-aug 4th, double-dim 6th Gx, Bbbb u5/N5 unter/neutral 5th uA
18 696.77 3/2 P5 perfect 5th A P5 perfect 5th A P5 perfect 5th A
19 735.48 32/21, 49/32, 20/13, 26/17, 192/125 ^5 up-5th ^A d6 dim 6th Bbb S5 super 5th SA
20 774.19 14/9, 11/7, 25/16 vm6 downminor 6th vBb A5 aug 5th A# sm6 subminor 6th sBb
21 812.90 8/5 m6 minor 6th Bb m6 minor 6th Bb m6 minor 6th Bb
22 851.61 18/11, 44/27, 13/8, 49/30, 80/49 ~6 mid 6th vB AA5, dd7 double-aug 5th, double-dim 7th Ax, Cbb N6 neutral 6th UBb/uB
23 890.32 5/3, 42/25 M6 major 6th B M6 major 6th B M6 major 6th B
24 929.03 12/7, 128/75 ^M6 upmajor 6th ^B d7 dim 7th Cb SM6 supermajor 6th SB
25 967.74 7/4, 125/72 vm7 downminor 7th vC A6 aug 6th B# sm7 subminor 7th sC
26 1006.45 16/9, 9/5, 34/19, 25/14 m7 minor 7th C m7 minor 7th C m7 minor 7th C
27 1045.16 11/6, 20/11, 64/35 ~7 mid 7th ^C AA6, dd8 double-aug 6th, double-dim 8ve Bx, Dbb N7 neutral 7th UC/uC#
28 1083.87 28/15, 15/8 M7 major 7th C# M7 major 7th C# M7 major 7th C#
29 1122.58 48/25, 40/21, 21/11, 44/23 ^M7 upmajor 7th ^C# d8 dim 8ve Db SM7 supermajor 7th SC#
30 1161.29 88/45, 96/49, 45/23, 125/64, 35/18 v8 down-8ve vD A7 aug 7th Cx s8/u8 sub 8th, unter 8ve sD/uD
31 1200.00 2/1 P8 perfect 8ve D P8 perfect 8ve D P8 perfect 8ve D

Interval quality and chord names in color notation

Combining ups and downs notation with color notation, qualities can be loosely associated with colors:

Quality Color name Monzo Format Examples
downminor zo [a b 0 1 7/6, 7/4
minor fourthward wa [a b where b < −1 32/27, 16/9
gu [a b -1 6/5, 9/5
mid ilo [a b 0 0 1 11/9, 11/6
lu [a b 0 0 -1 12/11, 18/11
major yo [a b 1 5/4, 5/3
fifthward wa [a b where b > 1 9/8, 27/16
upmajor ru [a b 0 -1 9/7, 12/7

All 31edo chords can be named using ups and downs. Alterations are always enclosed in parentheses, additions never are. An up, down or mid immediately after the chord root affects the 3rd, 6th, 7th, and/or the 11th (every other note of a stacked-3rds chord 6-1-3-5-7-9-11-13). Here are the zo, gu, ilo, yo and ru triads:

Color of the 3rd JI Chord Edosteps Notes of C Chord Written name Spoken name
zo 6:7:9 0 – 7 – 18 C – EHeQd3.svg – G Cvm C subminor
gu 10:12:15 0 – 8 – 18 C – E♭ – G Cm C minor
ilo 18:22:27 0 – 9 – 18 C – EHeQd1.svg – G C~ C neutral
yo 4:5:6 0 – 10 – 18 C – E – G C, Cmaj C, C major
ru 14:18:21 0 – 11 – 18 C – EHeQu1.svg – G C^ C supermajor

For a more complete list of chords, see 31edo Chord Names and Ups and Downs Notation #Chords and Chord Progressions.

Notation

Step Offset −4 −3 −2 −1 0 +1 +2 +3 +4
Symbol
Heji4.svg
HeQd3.svg
Heji11.svg
HeQd1.svg
Heji18.svg
HeQu1.svg
Heji25.svg
HeQu3.svg
Heji32.svg

Neutral circle-of-fifths notation

Neutral circle-of-fifths notation is much like ups and downs notation. Between C and D (do and re) for example, we have the following notes:

Degree Letter Name English full name
0 C do C
1 CHeQu1.svg do HeQu1.svg C half-sharp
2 C♯ do ♯ C sharp
3 D♭ re ♭ D flat
4 DHeQd1.svg re HeQd1.svg D half-flat
5 D re D

Circle-of-fifths notation

Circle-of-fifths notation uses double sharps and double flats:

Degree Letter Name English full name
0 C do C
1 D𝄫 re 𝄫 D double flat
2 C♯ do ♯ C sharp
3 D♭ re ♭ D flat
4 C𝄪 do 𝄪 C double sharp
5 D re D

While using double sharp and double flat may seem confusing because it alternates between C and D, it provides a way of writing chords that is consistent with traditional notation. For example, the subminor7 chord 12:14:18:21 is written like so:

  • C / D♯ / G / A♯
  • C♯ / D𝄪 / G♯ / A𝄪
  • D♭ / E / A♭ / B
  • D / E♯ / A / B♯

In 12edo, the enharmonic equivalences include C♯ = D♭, E♯ = F, and E = F♭. But in 31edo we have:

  • C𝄪 = DHeQd1.svg
  • D𝄫 = CHeQu1.svg
  • E♯ = FHeQd1.svg
  • F♭ = EHeQu1.svg
  • E𝄪 = FHeQu1.svg
  • F𝄫 = EHeQd1.svg

31edo can be notated with a seperate semi/sesqui sharp/flat chain (like 17edo), with its own enharmonic circle of fifths.

31edo CoF semi and sesqui.png

Sagittal notation

The Revo flavor of Sagittal notation from the appendix to The Sagittal Songbook by Jacob A. Barton:

31edo Sagittal.png

MisterShafXen's notation

31edo can be notated as follows: A A# Bb B B# Cb C C# Db D D# Eb E E# Fb F F# Gb G G# Hb H H# Ib I I# Jb J J#/Kb K K#/Ab A.

Relationship to 12edo

31edo’s circle of 31 fifths can be bent into a 12-spoked "spiral of fifths". This is possible because 18\31 is on the 7\12 kite in the scale tree. Stated another way, it is possible because the absolute value of 31edo’s dodeca-sharpness (edosteps per Pythagorean comma) is 1.

This "spiral of fifths" can be a useful construct for introducing 31edo to musicians unfamiliar with microtonal music. It may help composers and musicians to make visual sense of the notation, and to understand what size of a jump is likely to land them where compared to 12edo.

The two innermost and two outermost intervals on the spiral are duplicates, reflecting the fact that it is a repeating circle at heart and the spiral shape is only a helpful illusion.

31-edo spiral.png

Scales

MOS scales

The fact that 31edo has meantone diatonic and chromatic scales is well-known, but some other MOSes and MOS chains⁠ ⁠[clarification needed] are also useful:

  • 9\31, the neutral third, generates ultrasoft mosh and superhard dicotonic MOSes.
  • 11\31, the supermajor third or diminished fourth, generates a parahard sensoid scale with resolution from neutral thirds, sixths, and sevenths to perfect fourths, fifths, and octaves, and a semihard 3L 8s scale with a jagged-but-chromatic feel.
  • 12\31 generator generates a semihard oneirotonic scale, similar to the 5L 3s scale in 13edo but with the 9/8, 5/4 and 7/6 better in tune and with the flat fifth close to 19/13.
  • A chain of 5\31 whole tones is exceptionally rich in 4:5:7 chords, which are approximated very well in 31edo.
  • If you're fond of orwell tetrads (which are also found in 31edo's oneirotonic), you will like the 7\31 (271.0¢) subminor third generator. The ultrasoft 9-tone orwelloid (4L 5s) MOS could be treated as a 9-tone well temperament.
  • It has close approximations to 6edf (→ miracle) and 9edf (→ Carlos Alpha), fifth-equivalent equal divisions that hit many good JI approximations.

See #Rank-2 temperaments for a table of MOSes and their temperament interpretations.

Harmonic scales

31edo approximates Mode 8 of the harmonic series okay, but many intervals between the harmonics aren't distinguished, most importantly 9/8 (major tone) and 10/9 (minor tone), as 31EDO is a meantone temperament. The interval between the 8th and 11th harmonics is approximated okay, but the intervals between the 11th harmonic and closer harmonics such as the 12th and 9th harmonics are approximated even better. 31's version of 13/8 is quite wide and only vaguely suggests the 13-limit.

The steps are: 5 5 4 4 4 3 3 3.

Overtones in "Mode 8": 8 9 10 11 12 13 14 15 16
…as JI Ratio from 1/1: 1/1 9/8 5/4 11/8 3/2 13/8 7/4 15/8 2/1
…in cents: 0 203.9 386.3 551.3 702.0 840.5 968.8 1088.3 1200.0
Nearest degree of 31edo: 0 5 10 14 18 22 25 28 31
…in cents: 0 193.5 387.1 541.9 696.8 851.6 967.7 1083.9 1200.0

In mode 16, the most closely-matched harmonics are the composite ones, 21 and 25. Of the other harmonics:

  • 17 is sharp, like 13. In fact, the 17:13 ratio is matched within a tenth of a cent.
  • 19 is also sharp, like 13 and 17. The 19:17 ratio is about one cent sharp. 31edo could be considered a tuning of the 2.5.7.13.17.19 subgroup, on which it is consistent (see mercy temperament).
  • 23 is about as flat as 11. The chromatic semitone is about half a cent off from 23:22. 31edo could be considered a tuning of the 2.3.5.7.11.23 subgroup, on which it is consistent.
  • 27 is quite flat, as it's 3^3 and the error from the meantone fifths accumulates.
  • 29 and 31 are both very sharp, and intervals involving them are unlikely to play any major role.
Odd overtones in "Mode 16": 17 19 21 23 25 27 29 31
…as JI Ratio from 1/1: 17/16 19/16 21/16 23/16 25/16 27/16 29/16 31/16
…in cents: 105.0 297.5 470.8 628.3 772.6 905.9 1029.6 1145.0
Nearest degree of 31edo: 3 8 12 16 20 23 27 30
…in cents: 116.1 309.7 464.5 619.4 774.2 890.3 1045.1 1161.3

Various subsets

A large open list of subsets from 31edo that people have named:

Approximation to JI

alt : Your browser has no SVG support.
Selected 19-limit intervals approximated in 31edo

Interval mappings

The following tables show how 15-odd-limit intervals are represented in 31edo. Prime harmonics are in bold; inconsistent intervals are in italics.

15-odd-limit intervals in 31edo (direct approximation, even if inconsistent)
Interval and complement Error (abs, ¢) Error (rel, %)
1/1, 2/1 0.000 0.0
5/4, 8/5 0.783 2.0
11/9, 18/11 0.979 2.5
7/4, 8/7 1.084 2.8
7/5, 10/7 1.867 4.8
15/14, 28/15 3.314 8.6
7/6, 12/7 4.097 10.6
11/6, 12/11 4.202 10.9
15/8, 16/15 4.398 11.4
15/11, 22/15 4.985 12.9
3/2, 4/3 5.181 13.4
5/3, 6/5 5.964 15.4
11/7, 14/11 8.298 21.4
9/7, 14/9 9.278 24.0
11/8, 16/11 9.382 24.2
11/10, 20/11 10.166 26.3
13/10, 20/13 10.302 26.6
9/8, 16/9 10.362 26.8
13/8, 16/13 11.085 28.6
9/5, 10/9 11.145 28.8
13/7, 14/13 12.169 31.4
15/13, 26/15 15.483 40.0
13/12, 24/13 16.266 42.0
13/9, 18/13 17.263 44.6
13/11, 22/13 18.242 47.1
15-odd-limit intervals in 31edo (patent val mapping)
Interval and complement Error (abs, ¢) Error (rel, %)
1/1, 2/1 0.000 0.0
5/4, 8/5 0.783 2.0
11/9, 18/11 0.979 2.5
7/4, 8/7 1.084 2.8
7/5, 10/7 1.867 4.8
15/14, 28/15 3.314 8.6
7/6, 12/7 4.097 10.6
11/6, 12/11 4.202 10.9
15/8, 16/15 4.398 11.4
15/11, 22/15 4.985 12.9
3/2, 4/3 5.181 13.4
5/3, 6/5 5.964 15.4
11/7, 14/11 8.298 21.4
9/7, 14/9 9.278 24.0
11/8, 16/11 9.382 24.2
11/10, 20/11 10.166 26.3
13/10, 20/13 10.302 26.6
9/8, 16/9 10.362 26.8
13/8, 16/13 11.085 28.6
9/5, 10/9 11.145 28.8
13/7, 14/13 12.169 31.4
15/13, 26/15 15.483 40.0
13/12, 24/13 16.266 42.0
13/11, 22/13 20.468 52.9
13/9, 18/13 21.447 55.4

Regular temperament properties

Subgroup Comma list Mapping Optimal
8ve stretch (¢)
Tuning error
Absolute (¢) Relative (%)
2.3 [-49 31 [31 49]] +1.63 1.64 4.22
2.3.5 81/80, 393216/390625 [31 49 72]] +0.98 1.63 4.20
2.3.5.7 81/80, 126/125, 1029/1024 [31 49 72 87]] +0.83 1.43 3.70
2.3.5.7.11 81/80, 99/98, 121/120, 126/125 [31 49 72 87 107]] +1.21 1.49 3.84
2.3.5.7.11.13 66/65, 81/80, 99/98, 105/104, 121/120 [31 49 72 87 107 115]] +0.50 2.07 5.35

31et is lower in relative error than any previous equal temperaments in the 7-, 11-, 13-, and 17-limit. The next equal temperaments doing better in those subgroups are 72, 72, 41, and 46, respectively.

31edo excels in the 2.5.7 subgroup (the JI chord 4:5:7 is represented highly consistently: to distance 10.36). In 2.5.7 it tempers out the didacus comma 3136/3125 and the quince comma 823543/819200, thus also tempering out the very small rainy comma, the simplest 2.5.7 comma tempered out by the 7-limit microtemperament 171edo. In the 11-limit, 31edo can be defined as the unique temperament that tempers out 81/80, 99/98, 121/120, and 126/125, and it supports orwell, mohajira, and the relatively high-accuracy temperament miracle. In the 13-limit 31edo doesn't do as well, but is the optimal patent val for the rank five temperament tempering out the 13-limit comma 66/65, which equates 6/5 and 13/11. It also provides the optimal patent val for mohajira, squares and casablanca in the 11-limit and huygens/meantone, squares, winston, lupercalia and nightengale in the 13-limit. In the 17-limit it tempers out 120/119, equating the otonal tetrad of 4:5:6:7 and the inversion of the 10:12:15:17 minor tetrad.

Commas

31edo tempers out the following commas. This assumes the val 31 49 72 87 107 115], comma values rounded to 5 significant digits.

Prime
limit
Ratio[note 2] Monzo Cents Color name Name
3 (30 digits) [-49 31 160.605 Quadlawa 31-comma
5 (16 digits) [-25 7 6 31.567 Lala-tribiyo Ampersand
5 81/80 [-4 4 -1 21.506 Gu Syntonic comma
5 (12 digits) [17 1 -8 11.445 Saquadbigu Würschmidt comma
5 (14 digits) [-21 3 7 10.061 Lasepyo Semicomma
5 (24 digits) [38 -2 -15 1.3843 Sasa-quintrigu Hemithirds comma
7 59049/57344 [-13 10 0 -1 50.72 Laru Harrison's comma
7 3645/3584 [-9 6 1 -1 29.22 Laruyo Schismean comma
7 (18 digits) [-10 7 8 -7 22.413 Lasepru-aquadbiyo Blackjackisma
7 64827/64000 [-9 3 -3 4 22.227 Laquadzo-atrigu Squalentine comma
7 2430/2401 [1 5 1 -4 20.785 Quadru-ayo Nuwell comma
7 50421/50000 [-4 1 -5 5 14.516 Quinzogu Trimyna comma
7 126/125 [1 2 -3 1 13.795 Zotrigu Starling comma, septimal semicomma
7 1728/1715 [6 3 -1 -3 13.074 Trizo-agu Orwellisma
7 1029/1024 [-10 1 0 3 8.4327 Latrizo Gamelisma
7 225/224 [-5 2 2 -1 7.7115 Ruyoyo Marvel comma, septimal kleisma
7 16875/16807 [0 3 4 -5 6.9903 Quinru-aquadyo Mirkwai comma
7 3136/3125 [6 0 -5 2 6.0832 Zozoquingu Hemimean comma
7 6144/6125 [11 1 -3 -2 5.3621 Sarurutrigu Porwell comma
7 (18 digits) [-26 -1 1 9 3.7919 Latritrizo-ayo Wadisma
7 65625/65536 [-16 1 5 1 2.3495 Lazoquinyo Horwell comma
7 (12 digits) [-11 2 7 -3 1.6283 Latriru-asepyo Meter comma
7 2401/2400 [-5 -1 -2 4 0.72120 Bizozogu Breedsma
11 99/98 [-1 2 0 -2 1 17.576 Loruru Mothwellsma
11 121/120 [-3 -1 -1 0 2 14.367 Lologu Biyatisma
11 176/175 [4 0 -2 -1 1 9.8646 Lorugugu Valinorsma
11 243/242 [-1 5 0 0 -2 7.1391 Lulu Rastma
11 385/384 [-7 -1 1 1 1 4.5026 Lozoyo Keenanisma
11 441/440 [-3 2 -1 2 -1 3.9302 Luzozogu Werckisma
11 540/539 [2 3 1 -2 -1 3.2090 Lururuyo Swetisma
11 3025/3024 [-4 -3 2 -1 2 0.57240 Loloruyoyo Lehmerisma
13 105/104 [-3 1 1 1 0 -1 16.567 Thuzoyo Animist comma
13 144/143 [4 2 0 0 -1 -1 12.064 Thulu Grossma
13 196/195 [2 -1 -1 2 0 -1 8.8554 Thuzozogu Mynucuma
13 625/624 [-4 -1 4 0 0 -1 2.77 Thuquadyo Tunbarsma
13 1001/1000 [-3 0 -3 1 1 1 1.73 Tholozotrigu Fairytale comma, sinbadma
13 4096/4095 [12 -2 -1 -1 0 -1 0.42 Sathurugu Schismina

Rank-2 temperaments

Rank-2 temperaments by generators
Generator* Cents* Mos scales Temperaments Pergen
1\31 38.71 Slender (P8, P4/13)
2\31 77.42 1L 14s, 15L 1s Valentine / lupercalia (P8, P5/9)
3\31 116.13 1L 9s, 10L 1s, 10L 11s Mercy / miracle (P8, P5/6)
4\31 154.84 1L 6s, 7L 1s,
8L 7s, 8L 15s
Greeley / nusecond (P8, P11/11)
5\31 193.55 1L 5s, 6L 1s, 6L 7s,
6L 13s, 6L 19s
Luna / didacus / hemithirds /
hemiwürschmidt / tutone
(P8, ccP4/15)
6\31 232.26 1L 4s, 5L 1s, 5L 6s,
5L 11s, 5L 16s, 5L 21s
Mothra / mosura
Quadrawell
(P8, P5/3)
7\31 270.97 1L 3s, 4L 1s, 4L 5s,
9L 4s, 9L 13s
Orson / orwell / winston (P8, P12/7)
8\31 309.68 3L 1s, 4L 3s, 4L 7s,
4L 11s, 4L 15s, 4L 19s,
4L 23s
Myna
Triwell
(P8, ccP5/10)
9\31 348.39 3L 1s, 3L 4s, 7L 3s,
7L 10s, 7L 17s
Mohaha / vicentino /
mohajira / migration
(P8, P5/2)
10\31 387.10 3L 1s, 3L 4s, 3L 7s,
3L 10s, 3L 13s, 3L 16s,
3L 19s, 3L 22s, 3L 25s
Würschmidt / worschmidt (P8, ccP5/8)
11\31 425.81 3L 2s, 3L 5s, 3L 8s,
3L 11s, 14L 3s
Squares / sentinel (P8, P11/4)
12\31 464.52 3L 2s, 5L 3s,
5L 8s, 13L 5s
A-Team
Semisept
(P8, c5P4/14)
13\31 503.23 2L 3s, 5L 2s,
7L 5s, 12L 7s
Meantone / meanpop (P8, P5)
14\31 541.94 2L 3s, 2L 5s, 2L 7s,
9L 2s, 11L 9s
Casablanca
Cypress
Oracle
(P8, c5P4/12)
15\31 580.65 2L 3s, 2L 5s, 2L 7s,
2L 9s, 2L 11s, 2L 13s,
2L 15s, 2L 17s, 2L 19s,
2L 21s, 2L 23s, 2L 25s,
2L 27s
Tritonic / tritoni (P8, ccP4/5)

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

Instruments

Keyboard Instruments

String Instruments

Other Instruments

31edo array kalimba built by Tristan Bay; 3 octaves, 94 keys, and laid out in circle-of-fourths meantone tuning

Music

See also: Category:31edo tracks

See also

Notes

  1. Based on treating 31edo as a 23-limit temperament; other approaches are also possible.
  2. Ratios longer than 10 digits are presented by placeholders with informative hints.

Further reading

Books

Articles

External links

Websites

Videos

Software

Diagrams