Monkey

Revision as of 10:38, 15 April 2026 by FloraC (talk | contribs) (Complete interval table)

The monkey temperament is one of the 7-limit extensions of tetracot, the 5-limit temperament tempering out the tetracot comma (15625/15552), and is naturally a full 13-limit temperament.

Monkey
Subgroups 2.3.5.7, 2.3.5.7.11, 2.3.5.7.11.13
Comma basis 875/864, 5120/5103 (7-limit);
100/99, 243/242, 385/384 (11-limit)
100/99, 144/143, 243/242, 385/384
(13-limit)
Reduced mapping ⟨1; 4 9 -15 10 -2]
ET join 41 & 48
Generators (CWE) ~10/9 = 175.6 ¢
MOS scales 6L 1s, 7L 6s, 7L 13s, 7L 20s
Ploidacot tetracot
Minimax error 9-odd-limit: 6.68 ¢;
13-limit 21-odd-limit: 12.8 ¢
Target scale size 9-odd-limit: 27 notes;
13-limit 21-odd-limit: 34 notes

In addition to the tetracot comma, monkey tempers out 875/864, making it a keemic temperament. It also tempers out 5120/5103, making it a hemifamity temperament, so the septimal comma is equated with the syntonic comma. At 7 generator steps, this diesis-sized interval also represents 40/39, 45/44, 55/54, 65/64, 66/65, and 121/120 in the 2.3.5.7.13-subgroup version of tetracot, and divides the chromatic semitone in four. The same interval is now used to bridge septimal intervals with Pythagorean intervals alike.

Additionally, the generator can be taken to represent 21/19, which gives us an extension for prime 19 at -12 generator steps.

See Tetracot family #Monkey for technical data.

Interval chain

In the following tables, odd harmonics 1–13 and their inverses are in bold.

# Cents* Approximate ratios
0 0.0 1/1
1 175.6 11/10, 10/9
2 351.2 11/9, 16/13
3 526.9 15/11
4 702.5 3/2
5 878.1 5/3
6 1053.7 11/6, 24/13
7 29.4 40/39, 45/44, 55/54, 64/63
8 205.0 9/8
9 380.6 5/4
10 556.2 11/8, 18/13
11 731.8 20/13, 32/21
12 907.5 22/13
13 1083.1 13/7, 15/8
14 58.7 25/24, 27/26, 33/32, 36/35
15 234.3 8/7, 15/13
16 409.9 33/26
17 585.6 45/32, 88/63
18 761.2 25/16, 54/35
19 936.8 12/7
20 1112.4 40/21
21 88.1 22/21
22 263.7 75/64, 81/70
23 439.3 9/7
24 614.9 10/7
25 790.5 11/7
26 966.2 225/128, 243/140, 256/147
27 1141.8 27/14

* In 13-limit CWE tuning, octave reduced

Tunings

Tuning spectrum

Eigenmonzo
(unchanged-interval)
Generator (¢) Comments
11/10 165.004
11/9 173.704
14/13 174.746
12/11 174.894
11/8 175.132
14/11 175.300 11-odd-limit minimax
8/7 175.412
7/6 175.428
9/7 175.438
4/3 175.489
15/14 175.694
7/5 175.729 7, 9, 13 and 15-odd-limit minimax
13/11 175.899
16/15 176.021
5/4 176.257 5-odd-limit minimax
18/13 176.338
15/13 176.516
6/5 176.872
13/10 176.890
13/12 176.905
15/11 178.984
16/13 179.736
10/9 182.404