Squares: Difference between revisions

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{{Infobox Regtemp
| Title = Skwares; Squares
| Subgroups = 2.3.7, 2.3.7.11, 2.3.5.7.11
| Comma basis = [[19683/19208]] (2.3.7); <br> [[99/98]], [[243/242]] (2.3.7.11); <br> [[81/80]], [[99/98]], [[121/120]] (11-limit)
| Edo join 1 = 31 | Edo join 2 = 45
| Generator = 9/7 | Generator tuning = 426.0 | Optimization method = CWE
| MOS scales = [[3L 2s]], [[3L 5s]], [[3L 8s]], [[3L 11s]], [[14L 3s]]
| Mapping = 1; -4 -16 -9 -10
| Pergen = (P8, P11/4)
| Odd limit 1 = (2.3.7) 7 | Mistuning 1 = 4.7 | Complexity 1 = 11
| Odd limit 2 = 11 | Mistuning 2 = 10.8 | Complexity 2 = 17
}}
At its most basic level, '''squares''' can be thought of as a [[2.3.7 subgroup|2.3.7-subgroup]] temperament (sometimes called ''skwares''), generated by a flat [[~]][[9/7]] such that four of them stack to the perfect eleventh, [[8/3]], therefore [[tempering out]] the comma [[19683/19208]]. However, it is more natural to think of the temperament first as [[2.3.7.11 subgroup]], tempering out [[99/98]] so as to identify the generator with [[14/11]] in addition to 9/7 and so that two generators stack to the undecimal neutral sixth, [[18/11]], two of which are then identified with 8/3 due to tempering out [[243/242]]. This can also be thought of as an octavization of the 3.7.11-subgroup [[mintaka]] temperament by identifying [[2/1]] with a false octave corresponding to 99/49~243/121, in a manner similar to [[sensi]]'s relation to [[BPS]].
At its most basic level, '''squares''' can be thought of as a [[2.3.7 subgroup|2.3.7-subgroup]] temperament (sometimes called ''skwares''), generated by a flat [[~]][[9/7]] such that four of them stack to the perfect eleventh, [[8/3]], therefore [[tempering out]] the comma [[19683/19208]]. However, it is more natural to think of the temperament first as [[2.3.7.11 subgroup]], tempering out [[99/98]] so as to identify the generator with [[14/11]] in addition to 9/7 and so that two generators stack to the undecimal neutral sixth, [[18/11]], two of which are then identified with 8/3 due to tempering out [[243/242]]. This can also be thought of as an octavization of the 3.7.11-subgroup [[mintaka]] temperament by identifying [[2/1]] with a false octave corresponding to 99/49~243/121, in a manner similar to [[sensi]]'s relation to [[BPS]].



Revision as of 19:22, 22 November 2025

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At its most basic level, squares can be thought of as a 2.3.7-subgroup temperament (sometimes called skwares), generated by a flat ~9/7 such that four of them stack to the perfect eleventh, 8/3, therefore tempering out the comma 19683/19208. However, it is more natural to think of the temperament first as 2.3.7.11 subgroup, tempering out 99/98 so as to identify the generator with 14/11 in addition to 9/7 and so that two generators stack to the undecimal neutral sixth, 18/11, two of which are then identified with 8/3 due to tempering out 243/242. This can also be thought of as an octavization of the 3.7.11-subgroup mintaka temperament by identifying 2/1 with a false octave corresponding to 99/49~243/121, in a manner similar to sensi's relation to BPS.

However, since the fifth in skwares is tuned flat, it is very natural to combine the temperament with meantone to create full 11-limit squares, which additionally can be restricted to the 7-limit as the temperament with comma basis 81/80 and 2401/2400. This 11-limit temperament is considered below.

There is also a natural extension adding prime 23 by equating the generator to 23/18, and so finding 23 itself seven generators down, tempering out 162/161.

As for prime 13, the way to map it is less clear. The canonical squares mapping tempers out 144/143 in order to equate the tridecimal neutral sixth, 13/8, with 18/11, finding 13 two generators up, while agora tempers out 105/104 to equate 8/7 with 15/13, finding the 13th harmonic 29 generators down. These two mappings are enharmonically equivalent in 31edo. Finally, squad tempers out 351/343 (which is the same as 3.7.11.13 minalzidar's tempering of that prime) so that 13 is equated with (7/3)3, and found 15 generators down.

See Meantone family #Squares and No-fives subgroup temperaments #Skwares for more technical data.

Interval chain

In the following table, prime harmonics and subharmonics are labelled in bold.

# Cents* Approximate ratios
11-limit 13-limit extensions
Squares Squad Agora
0 0.0 1/1
1 425.6 9/7, 14/11 13/10
2 851.2 18/11, 33/20, 44/27 13/8 21/13
3 76.8 21/20, 28/27 27/26
4 502.4 4/3
5 928.0 12/7 22/13, 26/15
6 153.6 11/10, 12/11 13/12 14/13
7 579.2 7/5 18/13
8 1004.8 9/5, 16/9
9 230.4 8/7 15/13
10 656.0 16/11, 22/15 13/9
11 1081.6 28/15 13/7 24/13
12 307.2 6/5 13/11
13 732.8 32/21 20/13
14 1158.4 49/25, 64/33, 96/49 52/27
15 384.0 56/45 26/21 16/13
16 809.6 8/5 21/13
17 35.2 36/35, 64/63

* In 11-limit CTE tuning

Scales

Tunings

7-limit norm-based tunings
Euclidean
Constrained Constrained & skewed Destretched
Tenney CTE: ~14/9 = 774.3052 ¢ CWE: ~14/9 = 774.1560 ¢ POTE: ~14/9 = 774.0585 ¢
11-limit norm-based tunings
Euclidean
Constrained Constrained & skewed Destretched
Tenney CTE: ~11/7 = 774.4005 ¢ CWE: ~11/7 = 774.1754 ¢ POTE: ~11/7 = 774.0427 ¢

Music

Joel Kivelä
Chris Vaisvil