Father family
The father family of rank-2 temperaments tempers out 16/15, the just diatonic semitone. This equates 4/3 with 5/4, so these are "fourth-thirds", or father, temperaments. In a sense, what father is all about is using semisixths or subfourths and pretending that is 5-limit, and like any temperament which seems to involve pretending, father is at the edge of what can sensibly be called a temperament at all. In other words, it is an exotemperament.
Father
Subgroup: 2.3.5
Comma list: 16/15
Mapping: [⟨1 0 4], ⟨0 1 -1]]
- mapping generators: ~2, ~3
- 5-odd-limit: ~3/2 = [1 1/2 -1/2⟩
Optimal ET sequence: 1, 2, 3, 5, 8, 13c, 21bcc
Badness: 0.014884
Overview to extensions
Strong extensions of father to include an approximation of harmonic 7 are septimal father (5 & 8d), mother (2 & 3), and pater (3 & 5d), all considered below.
Temperaments discussed elsewhere include:
Septimal father
Subgroup: 2.3.5.7
Comma list: 16/15, 28/27
Mapping: [⟨1 0 4 -2], ⟨0 1 -1 3]]
Wedgie: ⟨⟨ 1 -1 3 -4 2 10 ]]
- 7-odd-limit: ~3/2 = [1/2 0 -1/4 1/4⟩
- 9-odd-limit: ~3/2 = [1 -2 0 1⟩ = 14/9
Optimal ET sequence: 2d, 3d, 5, 8d, 13cd, 21bccdd
Badness: 0.021312
11-limit
Subgroup: 2.3.5.7.11
Comma list: 16/15, 22/21, 28/27
Mapping: [⟨1 0 4 -2 -3], ⟨0 1 -1 3 4]]
Optimal tunings:
- CTE: ~2 = 1\1, ~3/2 = 732.2094
- POTE: ~2 = 1\1, ~3/2 = 747.156
Optimal ET sequence: 2de, 3de, 5, 8d
Badness: 0.020589
Mother
Subgroup: 2.3.5.7
Comma list: 16/15, 21/20
Mapping: [⟨1 0 4 6], ⟨0 1 -1 -2]]
Wedgie: ⟨⟨ 1 -1 -2 -4 -6 -2 ]]
Optimal ET sequence: 2, 3, 5
Badness: 0.024152
11-limit
Subgroup: 2.3.5.7.11
Comma list: 11/10, 16/15, 21/20
Mapping: [⟨1 0 4 6 5], ⟨0 1 -1 -2 -1]]
Optimal tunings:
- CTE: ~2 = 1\1, ~3/2 = 721.6985
- POTE: ~2 = 1\1, ~3/2 = 717.364
Badness: 0.021957
Pater
Subgroup: 2.3.5.7
Comma list: 16/15, 126/125
Mapping: [⟨1 0 4 11], ⟨0 1 -1 -5]]
Wedgie: ⟨⟨ 1 -1 -5 -4 -11 -9 ]]
Optimal ET sequence: 3, 5d, 8d, 27bbccdd
Badness: 0.053001
11-limit
Subgroup: 2.3.5.7.11
Comma list: 16/15, 22/21, 100/99
Mapping: [⟨1 0 4 11 10], ⟨0 1 -1 -5 -4]]
Optimal tunings:
- CTE: ~2 = 1\1, ~3/2 = 761.8715
- POTE: ~2 = 1\1, ~3/2 = 751.396
Optimal ET sequence: 3, 5de, 8d
Badness: 0.035487