Pentacircle clan

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The pentacircle clan of rank-3 temperaments tempers out the pentacircle comma, 896/891. This has the effect of identifying 14/11 at the Pythagorean major third.

For the rank-4 pentacircle temperament, see Rank-4 temperament #Pentacircle (896/891).

Parapythic

Parapyth, by the original definition, is the 2.3.7.11.13 subgroup temperament tempering out 352/351 and 364/363. We begin by looking at the 2.3.7.11 restriction thereof.

Subgroup: 2.3.7.11

Comma list: 896/891

Mapping[1 0 0 7], 0 1 0 -4], 0 0 1 1]]

sval mapping generators: ~2, ~3, ~7

Optimal tuning (POTE): ~2 = 1\1, ~3/2 = 703.8345, ~7/4 = 969.8722

Optimal ET sequence12, 17, 36, 41, 58, 63, 104, 225e, 266e, 370bee, 699bbdeee

Badness: 0.0205 × 10-3

Overview to extensions

Subgroup extensions

By tempering out 896/891, we have mapped 14/11 to the major third, suggesting a slightly sharp fifth. This makes the minor third very close to the flat-of-Pythagorean 13/11, and extending the temperament to include harmonic 13 this way implies we temper out 352/351. In fact, 896/891 = (352/351)(364/363), so it is a very natural interpretation, giving rise to the 2.3.7.11.13 subgroup temperament shown below.

Full 11-limit extensions

The second comma in the comma list determines how we extend parapyth to include the harmonic 5.

Pele adds 441/440 and finds the harmonic 5 by equating the syntonic comma (81/80) with the septimal comma (64/63). Together with the slightly sharp fifth this extension makes for one of the most natural interpretations. Sensamagic adds 245/243 or 385/384, a traditional RTT favorite. Apollo adds 100/99 or 225/224, and is even simpler than sensamagic. Uni adds 540/539. Melpomene adds 56/55 or 81/80. Terrapyth adds 585640/583443, a complex entry that finds the harmonic 5 at the triple augmented unison (AAA1). These all have the same lattice structure as parapyth.

Julius aka varda adds 176/175, splitting the octave into two. Parahemif adds 243/242, splitting the perfect fifth into two. Kujuku adds 14700/14641, splitting the perfect twelfth into two. Tolerant adds 2200/2187, splitting the ~33/32 into two. Finally, canta adds 472392/471625, splitting the ~14/9 into three.

Temperaments discussed elsewhere are:

Considered below are tolerant, kujuku, and terrapyth.

Parapyth

Subgroup: 2.3.7.11.13

Comma list: 352/351, 364/363

Sval mapping: [1 0 0 7 12], 0 1 0 -4 -7], 0 0 1 1 1]]

Optimal tuning (POTE): ~2 = 1\1, ~3/2 = 703.8563, ~7/4 = 969.9074

Optimal ET sequence12f, 17, 41, 46, 58, 87, 104, 266ef, 329bef, 370beef, 474beef, 595bdeeeff, 699bbdeeeff

Badness: 0.101 × 10-3

Etypyth

Subgroup: 2.3.7.11.13.17

Comma list: 352/351, 364/363, 442/441

Sval mapping: [1 0 0 7 12 -13], 0 1 0 -4 -7 9], 0 0 1 1 1 1]]

Optimal tuning (POTE): ~2 = 1\1, ~3/2 = 704.0315, ~7/4 = 970.6051

Optimal ET sequence12f, 17g, 29g, 41g, 46, 58, 75e, 104, 121, 225e

Badness: 0.325 × 10-3

Terrapyth

Terrapyth tempers out the leapday comma, and can be described as 29 & 46 & 121.

Subgroup: 2.3.5.7.11

Comma list: 896/891, 585640/583443

Mapping: [1 0 -31 0 7], 0 1 21 0 -4], 0 0 0 1 1]]

mapping generators: ~2, ~3, ~7

Optimal tuning (POTE): ~2 = 1\1, ~3/2 = 704.1814, ~7/4 = 970.6217

Optimal ET sequence17c, 29, 46, 92de, 121, 167, 288be

Badness: 5.35 × 10-3

13-limit

Subgroup: 2.3.5.7.11.13

Comma list: 352/351, 364/363, 9295/9261

Mapping: [1 0 -31 0 7 12], 0 1 0 21 0 4 -7], 0 0 0 1 1 1]]

Optimal tuning (POTE): ~2 = 1\1, ~3/2 = 704.1691, ~7/4 = 970.8432

Optimal ET sequence17c, 29, 46, 75e, 92def, 121, 167, 288be

Badness: 2.48 × 10-3

17-limit

Subgroup: 2.3.5.7.11.13.17

Comma list: 352/351, 364/363, 442/441, 715/714

Mapping: [1 0 -31 0 7 12 -13], 0 1 0 21 0 4 -7 9], 0 0 0 1 1 1 1 1]]

Optimal tuning (POTE): ~2 = 1\1, ~3/2 = 704.1628, ~7/4 = 970.6620

Optimal ET sequence17cg, 29g, 46, 75e, 92defg, 121, 167, 288beg

Badness: 1.52 × 10-3

Tolerant

7-limit

Subgroup: 2.3.5.7

Comma list: 179200/177147

Mapping[1 0 0 -10], 0 1 0 11], 0 0 1 -2]]

mapping generators: ~2, ~3, ~5

Optimal tuning (POTE): ~2 = 1\1, ~3/2 = 703.9571, ~5/4 = 386.8863

Optimal ET sequence41, 80, 87, 121, 167, 208, 329b, 375b, 537b, 583b, 704bd

Badness: 0.165 × 10-3

11-limit

Subgroup: 2.3.5.7.11

Comma list: 896/891, 2200/2187

Mapping[1 0 0 -10 -3], 0 1 0 11 7], 0 0 1 -2 -2]]

Optimal tuning (POTE): ~2 = 1\1, ~3/2 = 704.0412, ~5/4 = 387.2927

Optimal ET sequence41, 80, 87, 121, 167, 208, 334be, 375be, 542bce

Badness: 1.039 × 10-3

13-limit

Subgroup: 2.3.5.7.11.13

Comma list: 325/324, 352/351, 364/363

Mapping: [1 0 0 -10 -3 2], 0 1 0 11 7 4], 0 0 1 -2 -2 -2]]

Optimal tuning (POTE): ~2 = 1\1, ~3/2 = 703.9605, ~5/4 = 386.9831

Optimal ET sequence41, 46, 80, 87, 121, 167, 208, 375be, 583bef

Badness: 1.021 × 10-3

17-limit

Subgroup: 2.3.5.7.11.13.17

Comma list: 256/255, 325/324, 352/351, 364/363

Mapping: [1 0 0 -10 -3 2 8], 0 1 0 11 7 4 -1], 0 0 1 -2 -2 -2 -1]]

Optimal tuning (POTE): ~2 = 1\1, ~3/2 = 704.0831, ~5/4 = 387.3269

Optimal ET sequence41, 46, 75e, 80, 87, 121, 167, 288beg

Badness: 0.982 × 10-3

Kujuku

Kujuku splits the perfect twelfth into two. Scott Dakota has aliased this temperament SQPP (for semiquartal parapyth).

Subgroup: 2.3.5.7.11

Comma list: 896/891, 14700/14641

Mapping[1 0 0 -13 -6], 0 2 0 17 9], 0 0 1 1 1]]

mapping generators: ~2, ~121/70, ~5

Optimal tuning (CTE): ~2 = 1\1, ~121/70 = 951.4956, ~5/4 = 386.7868

Optimal ET sequence24, 29, 34d, 53d, 58, 87, 121, 145, 179e, 208, 266e

Badness: 2.26 × 10-3

13-limit

Subgroup: 2.3.5.7.11.13

Comma list: 352/351, 364/363, 676/675

Mapping: [1 0 0 -13 -6 -1], 0 2 0 17 9 3], 0 0 1 1 1 1]]

Optimal tuning (CTE): ~2 = 1\1, ~26/15 = 951.8367, ~5/4 = 386.4048

Optimal ET sequence24, 29, 34d, 53d, 58, 87, 121, 179ef, 208, 266ef, 474beef

Badness: 1.06 × 10-3

Complexity spectrum: 15/13, 4/3, 13/10, 9/8, 13/11, 15/11, 12/11, 11/9, 11/8, 14/11, 16/13, 16/15, 11/10, 13/12, 9/7, 5/4, 18/13, 7/6, 6/5, 8/7, 10/9, 14/13, 15/14, 7/5

17-limit

Subgroup: 2.3.5.7.11.13.17

Comma list: 256/255, 352/351, 364/363, 676/675

Mapping: [1 0 0 -13 -6 -1 8], 0 2 0 17 9 3 -2], 0 0 1 1 1 1 -1]]

Optimal tuning (CTE): ~2 = 1\1, ~26/15 = 951.8015, ~5/4 = 386.9912

Optimal ET sequence24, 34d, 58, 87, 121, 179ef, 208g, 266efg

Badness: 1.24 × 10-3