No-twos subgroup temperaments

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Revision as of 13:51, 21 May 2024 by Dummy index (talk | contribs) (+overview, like a extension of "3.5 subgroup no-comma family")
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(WIP, catalog of 3.5.7 subgroup rank two temperaments will eventually be redirected here)

This is a collection of subgroup temperaments which omit the prime harmonic of 2. Because of the absence of octaves, these are all nonoctave scales using a period of a tritave, or if harmonic 3 is also excluded, 5/1.

Overview by mapping of 5

Classified by focusing on the mapping of 5th harmonic, similar to Rank-2 temperaments by mapping of 3.

  • Arcturus, Aldebaran and Polaris are with 3/1 period and ~5/3 generator. There is one-to-one correspondence between 3.5 subgroup and mapped intervals.
  • BPS is with a ~9/7 generator, two of which give the ~5/3.
  • Sirius is with a ~25/21 generator, three of which give the ~5/3.
  • Deneb is with a ~11/9 generator, three of which give the ~9/5.
  • Canopus is with a ~7/5 generator, five of which give the ~27/5 (9/5 and an tritave).
  • Alnilam is with a ~81/55 generator, ten of which give the ~243/5 (9/5 and three tritave).
  • Izar is with a ~16807/10125 generator, twelve of which give the ~2187/5 (9/5 and five tritave).

Arcturus

see Arcturus, Arcturus clan

Subgroup: 3.5.7

Comma list: 15625/15309

Sval mapping: [1 0 -7], 0 1 6]]

Sval mapping generators: ~3, ~5

POTE generator: ~5/3 = 878.042

Optimal ET sequence: b2, b11, b13

Aldebaran

see Aldebaran

Subgroup: 3.5.13

Comma list: 3159/3125

Mapping: [1 0 5], 0 1 -2]]

Supporting ETs: 15, 17, 13, 32, 47, 28, 11[-13], 19[+13], 43, 9[-13], 7[-13], 49[+13], 21[+13], 41[-13]

CTE generator: ~5/3 = 887.76

BPS

Subgroup: 3.5.7

Comma list: 245/243

Sval mapping: [1 1 2], 0 -2 1]]

Sval mapping generators: ~3, ~9/7

Optimal tuning (POTE): ~3 = 1\1edt, ~9/7 = 440.4881

Optimal ET sequence: b4, b9, b13, b56, b69, b82, b95

Canopus

Subgroup: 3.5.7

Comma list: 16875/16807

Subgroup-val mapping[1 3 3], 0 -5 -4]]

Sval mapping generators: ~3, ~7/5

Optimal tuning (CTE): ~3 = 1\1edt, ~7/5 = 584.017

Supporting ETs: b13, b10, b75, b62, b23, b49, b36, b16, b7cd, 29, b42c, b19cd, b33cd, b55c

Izar

Subgroup: 3.5.7

Comma list: 13841287201/13839609375

Subgroup-val mapping[1 7 5], 0 -12 -7]]

Sval mapping generators: ~3, ~16807/10125

Optimal tuning (CTE): ~3 = 1\1edt, ~16807/10125 = 877.280

Supporting ETs: b13, b11cd, b193, b15cd, b180, b24c, b167, b37c, b154, 141, b50c, b28cd, b128, b63c

No-twos-or-threes subgroup temperaments

Antipyth

see Antipyth

Subgroup: 5.7.11

Comma list: 859375/823543

Subgroup-val mapping[1 2 7], 0 1 7]]

Mapping generators: ~5, ~7/25

Optimal tuning (CTE): ~5 = 1\1ed5, ~7/5 = 592.728

Supporting ETs: c14, c5, c19, c33, c47, c9e, c61, c75, c23e, c24e, c52e, c80e, c89e, c37e

Juggernaut

Subgroup: 5.7.11

Comma list: 125/121

Subgroup-val mapping[2 4 3], 0 1 0]]

Mapping generators: ~11/5, ~7/25

Optimal tuning (CTE): ~11/5 = 1\2ed5, ~7/5 = 582.512

Supporting ETs: c14, c10, c6, c18, c24, c22, c32, c16, c38, c8d, c34, c26d, c46, c52e

No-twos-or-threes 13-limit

Subgroup: 5.7.11.13

Comma list: 125/121, 637/625

Subgroup-val mapping[2 4 3 0], 0 1 0 -2]]

Mapping generators: ~11/5, ~7/25

Optimal tuning (CTE): ~11/5 = 1\2ed5, ~7/5 = 582.512

Supporting ETs: c10, c14, c6, c24, c34, c16f, c44, c18f, c38, c26f, c54, c64

Graphs

357plot_cplx_damage.png
Complexity vs. damage plot. z<1 corresponds to the "Middle Path" inclusion criterion.

Projective tuning space diagrams

Temperaments with smaller commas, labeled by name
Temperaments with smaller commas, labeled by comma
Temperaments with larger commas, labeled by name
Temperaments with larger commas, labeled by comma
Both sets, labeled by name
Both sets, labeled by comma

11.675