Pentacircle clan

(Redirected from Pentacircle temperaments)

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

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

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

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

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

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

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

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

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

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

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

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

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

Trienparapyth

Trienparapyth can be described as the no-17's 23-limit 80 & 87 & 109 temperament. It splits the ~4/3 generator of parapythic into three ~11/10's by tempering out 4000/3993 in the 11-limit and it interprets (11/10)2 accurately as 23/19 in its full subgroup, tempering out 2300/2299, or optionally less accurately as ~17/14, though because this mapping only really makes much sense in 80edo it is not included here; however, its connection to parapyth structure comes from later in the generator chain; specifically, from (11/10)7 onwards. We may simplify (11/10)7 as (4/3)2(11/10) = 88/45, the octave-complement of 45/44. Notice that parapythic wants a slightly flat ~4/3 corresponding to an 11/10 being tuned anywhere from around just (in an extremely sharp-for-parapyth tuning) to a little less than 1-cent sharp, a very narrow tuning range; therefore 88/45 is flattened so that 2/(11/10)7~45/44 is sharpened so that we can equate it with 40/39, tempering out (40/39)/(45/44) = 352/351, and because we know we want prime 19 later on, we equate this with 39/38 by tempering out the pinkanberry, 1521/1520. Next, for eight generator steps, observe that (11/10)9/(11/10)/2 = (4/3)3/(11/10)/2 = (32/27)/(11/10) = 320/297 is sharp of 15/14 by 896/891, which is reasonable to equate it with because in an optimal tuning 11/10 will be very slightly sharp so that the interval of eight generator steps is eight times as sharp. Thus, tempering out 896/891 and 4000/3993 defines trienparapyth in the 11-limit, which also tempers out 3388/3375, the 13-limit adds 352/351, the no-17's 19-limit equates 40/39 with 39/38 and the no-17's 23-limit equates 23/19 with (11/10)2 as already mentioned.

Structurally, trienparapyth is three copies of parapyth with the independent generator of 7 connected to an equivalent independent generator for 5 through the ~15/7 reached at (11/10)8 so that ~20/7 is reached at (11/10)11, and this is how the last generator can be either 5 or 7.

Subgroup: 2.3.5.7.11

Comma list: 896/891, 3388/3375

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

mapping generators: ~2, ~11/10, ~5
• CTE: ~2 = 1\1, ~11/10 = 165.4134, ~5/4 = 386.8872
• CWE: ~2 = 1\1, ~11/10 = 165.3593, ~5/4 = 387.8093

13-limit

Subgroup: 2.3.5.7.11.13

Comma list: 352/351, 364/363, 1001/1000

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

mapping generators: ~2, ~11/10, ~5

Optimal tunings:

• CTE: ~2 = 1\1, ~11/10 = 165.3975, ~5/4 = 386.7908
• CWE: ~2 = 1\1, ~11/10 = 165.3802, ~5/4 = 387.8759

Optimal ET sequence: 7d, 22, 29, 51f, 51cde, 58, 80, 87, 145, 167, 225ce, 254, 312ce

2.3.5.7.11.13.19 subgroup

Note 109edo is a good patent val tuning not listed in the optimal ET sequence here.

Subgroup: 2.3.5.7.11.13.19

Comma list: 286/285, 352/351, 364/363, 400/399

Mapping: [1 2 0 2 1 0 0], 0 -3 0 -11 1 10 14], 0 0 1 1 1 1 1]]

mapping generators: ~2, ~11/10, ~5

Optimal tunings:

• CTE: ~2 = 1\1, ~11/10 = 165.2990, ~5/4 = 386.3154
• CWE: ~2 = 1\1, ~11/10 = 165.2976, ~5/4 = 387.7451

Optimal ET sequence: 7d, 22, 29, 51fh, 51cde, 58h, 80, 87, 138cdeh, 167h

2.3.5.7.11.13.19.23 subgroup

Subgroup: 2.3.5.7.11.13.19.23

Comma list: 208/207, 286/285, 352/351, 364/363, 400/399

Mapping: [1 2 0 2 1 0 0 0], 0 -3 0 -11 1 10 14 16], 0 0 1 1 1 1 1 1]]

mapping generators: ~2, ~11/10, ~5

Optimal tunings

• CTE: ~2 = 1\1, ~11/10 = 165.2579, ~5/4 = 386.1446
• CWE: ~2 = 1\1, ~11/10 = 165.2679, ~5/4 = 387.7240

Optimal ET sequence: 22i, 29, 51fhi, 51cde, 58hi, 80, 87, 109, 138cdehi, 167hi