ABACABA JI scales: Difference between revisions
m {{Navbox scale gallery}} |
|||
| (13 intermediate revisions by 2 users not shown) | |||
| Line 1: | Line 1: | ||
ABACABA is the | ABACABA is the ternary [[Fraenkel word]], or the rank-3 power SNS, i.e., the (4, 2, 1) [[SN scale|SNS]] pattern, and the singular [[Rank-3 scale#Pairwise well-formed scales|pairwise well-formed]] generalized step pattern. Such scales can be thought of as mirror-symmetric ([[Chirality|achiral]]) tetrachordal scales. As [[step-nested scales]], all ABACABA scales can be described as SNS (P, P/T, T/A), or equivalently as SNS (P, T, A) etc., where P is the period, and T = ABA, the outer interval of the tetrachord. When they span a 2/1 period (P=2), scales with this step pattern are known as Cantor-2 scales. | ||
== 225-limit ABACABA scales with period 2/1, with steps > 20c == | == 225-limit ABACABA scales with period 2/1, with steps > 20c == | ||
225 is chosen as the [[odd-limit]] so that the list includes all ABACABA scales with complexity up to that of the [[5-limit]] double harmonic major scale — [[SNS (2/1, 3/2, 5/4)-7|16/15 5/4 4/3 3/2 8/5 15/8 2/1]] — and a lower limit of 20c for step sizes is chosen so that there are no steps smaller than [[81/80]]. For ABACABA scales, 225-odd-limit implies 13-limit. | 225 is chosen as the [[odd-limit]] so that the list includes all ABACABA scales with complexity up to that of the [[5-limit]] double harmonic major scale — [[SNS (2/1, 3/2, 5/4)-7|16/15 5/4 4/3 3/2 8/5 15/8 2/1]] — and a lower limit of 20c for step sizes is chosen so that there are no steps smaller than [[81/80]]. For ABACABA scales, 225-odd-limit implies 13-limit. | ||
| Line 1,632: | Line 1,632: | ||
|} | |} | ||
== 729-limit | == 729-limit ABACABA scales with period 3/2, with steps > 20c == | ||
Given the scales repeat at 3/2, factors of 3 in the odd-limit vary with transposition by a period. Accordingly the odd-limit listed is the odd-limit for intervals in a single period of the scale. There are no 729-limit ABACABA scales with period 3/2, with steps > 20c. The list has an effective odd-limit of 675. | Given the scales repeat at 3/2, factors of 3 in the odd-limit vary with transposition by a period. Accordingly the odd-limit listed is the odd-limit for intervals in a single period of the scale. There are no 729-limit ABACABA scales with period 3/2, with steps > 20c. The list has an effective odd-limit of 675. | ||
=== Tetrachord to | === Tetrachord to 9/8 -> C = 32/27 (~294.13c) === | ||
{| class="wikitable" | {| class="wikitable" | ||
|+ | |+ | ||
| Line 1,644: | Line 1,644: | ||
|- | |- | ||
|21/20 (~84.47c) | |21/20 (~84.47c) | ||
| | |50/49 (~34.98c) | ||
|1/1 21/20 8/7 | |1/1 21/20 15/14 9/8 4/3 7/5 10/7 2/1 | ||
|147 | |147 | ||
|- | |- | ||
| | |27/26 (~65.34c) | ||
| | |169/162 (~73.24c) | ||
|1/1 | |1/1 27/26 13/12 9/8 4/3 18/13 13/9 3/2 | ||
| | |243 | ||
|- | |- | ||
| | |25/24 (~70.67c) | ||
| | |648/625 (~62.57c) | ||
|1/1 27/25 | |1/1 25/24 27/25 9/8 4/3 25/18 36/25 3/2 | ||
|625 | |625 | ||
|- | |} | ||
|16 | |||
| | === Tetrachord to 17/14 -> C = 294/289 (~29.70c) === | ||
|1/1 16/ | {| class="wikitable" | ||
| | |+ | ||
|- | !A | ||
| | !B | ||
| | !Scale | ||
|1/1 | !odd-limit of scale intervals | ||
|675 | |- | ||
|17/16 (~104.96c) | |||
|128/117 (~115.56c) | |||
|1/1 17/16 8/7 17/14 28/17 21/16 24/17 3/2 | |||
|357 | |||
|- | |||
|15/14 (~119.44c) | |||
|238/225 (~97.24c) | |||
|1/1 15/14 17/15 17/14 28/17 45/34 7/5 3/2 | |||
|675 | |||
|} | |} | ||
| Line 1,676: | Line 1,685: | ||
!Scale | !Scale | ||
!odd-limit of scale intervals | !odd-limit of scale intervals | ||
|- | |- | ||
|19/18 (~93.60c) | |19/18 (~93.60c) | ||
| Line 1,686: | Line 1,690: | ||
|1/1 19/18 21/19 7/6 9/7 19/14 27/19 3/2 | |1/1 19/18 21/19 7/6 9/7 19/14 27/19 3/2 | ||
|361 | |361 | ||
|- | |||
|21/20 (~84.47c) | |||
|200/189 (~97.94c) | |||
|1/1 21/20 10/9 7/6 9/7 27/20 10/7 3/2 | |||
|567 | |||
|} | |} | ||
=== Tetrachord to | === Tetrachord to 19/16 -> C = 384/361 (~106.93c) === | ||
{| class="wikitable" | {| class="wikitable" | ||
|+ | |+ | ||
| Line 1,696: | Line 1,705: | ||
!odd-limit of scale intervals | !odd-limit of scale intervals | ||
|- | |- | ||
| | |19/18 (~93.60c) | ||
| | |81/76 (~110.31c) | ||
|1/1 | |1/1 19/18 9/8 19/16 24/19 4/3 27/19 3/2 | ||
|361 | |||
| | |||
|} | |} | ||
=== Tetrachord to | === Tetrachord to 6/5 -> C = 25/24 (~70.67c) === | ||
{| class="wikitable" | {| class="wikitable" | ||
|+ | |+ | ||
| Line 1,715: | Line 1,719: | ||
!odd-limit of scale intervals | !odd-limit of scale intervals | ||
|- | |- | ||
| | |21/20 (~84.47c) | ||
| | |160/147 (~146.71c) | ||
|1/1 | |1/1 21/20 8/7 6/5 5/4 21/16 10/7 3/2 | ||
| | |441 | ||
| | |- | ||
|24/23 (~73.68c) | |||
|529/480 (~168.28c) | |||
|1/1 24/23 23/20 6/5 5/4 30/23 23/16 3/2 | |||
| | |529 | ||
|- | |- | ||
| | |16/15 (~111.73c) | ||
|128 | |135/128 (~92.18c) | ||
|1/1 | |1/1 16/15 9/8 6/5 5/4 4/3 45/32 3/2 | ||
| | |675 | ||
|- | |- | ||
| | |18/17 (~98.95c) | ||
| | |289/270 (~117.73c) | ||
|1/1 | |1/1 18/17 17/15 6/5 5/4 45/34 17/12 3/2 | ||
|675 | |675 | ||
|- | |||
|27/25 (~133.24c) | |||
|250/243 (~49.17c) | |||
|1/1 27/25 10/9 6/5 5/4 27/20 25/18 3/2 | |||
|729 | |||
|} | |} | ||
=== Tetrachord to | === Tetrachord to 27/23 -> C = 529/486 (~146.77c) === | ||
{| class="wikitable" | {| class="wikitable" | ||
|+ | |+ | ||
| Line 1,748: | Line 1,753: | ||
!odd-limit of scale intervals | !odd-limit of scale intervals | ||
|- | |- | ||
| | |24/23 (~73.68c) | ||
| | |69/64 (~130.23c) | ||
|1/1 | |1/1 24/23 9/8 27/23 23/18 4/3 23/16 3/2 | ||
|529 | |||
| | |||
|} | |} | ||
| Line 1,782: | Line 1,773: | ||
|} | |} | ||
=== Tetrachord to | === Tetrachord to 25/22 -> C = 726/625 (~259.34c) === | ||
{| class="wikitable" | {| class="wikitable" | ||
|+ | |+ | ||
| Line 1,790: | Line 1,781: | ||
!odd-limit of scale intervals | !odd-limit of scale intervals | ||
|- | |- | ||
|24 | |25/24 (~70.67c) | ||
| | |288/275 (~79.96c) | ||
|1/1 24/ | |1/1 25/24 12/11 25/22 33/25 11/8 36/25 3/2 | ||
| | |625 | ||
|} | |} | ||
=== Tetrachord to | === Tetrachord to 10/9 -> C = 243/200 (~337.15c) === | ||
{| class="wikitable" | {| class="wikitable" | ||
|+ | |+ | ||
| Line 1,805: | Line 1,796: | ||
|- | |- | ||
|25/24 (~70.67c) | |25/24 (~70.67c) | ||
| | |128/125 (~41.06c) | ||
|1/1 25/24 | |1/1 25/24 16/15 10/9 27/20 45/32 36/25 3/2 | ||
|675 | |675 | ||
|} | |} | ||
=== Tetrachord to | === Tetrachord to 15/13 -> C = 169/150 (~206.47c) === | ||
{| class="wikitable" | {| class="wikitable" | ||
|+ | |+ | ||
| Line 1,832: | Line 1,809: | ||
!odd-limit of scale intervals | !odd-limit of scale intervals | ||
|- | |- | ||
| | |27/26 (~65.34c) | ||
| | |260/243 (~117.07c) | ||
|1/1 | |1/1 27/26 10/9 15/13 39/30 27/20 13/9 3/2 | ||
| | |729 | ||
|} | |} | ||
== 729-limit | == 729-limit ABACABA scales with period 4/3, with steps > 20c == | ||
2/1 period scales with two periods of these ABACABA scales and a remaining interval of 9/8 may be built, akin to octave species scales built of two copies of a tetrachord (with a 9/8 remainder). The remaining 9/8 interval may be filled in a number of different ways. There are no 729-limit ABACABA scales with period 4/3, with steps > 20c. The list has an effective odd-limit of 675. | 2/1 period scales with two periods of these ABACABA scales and a remaining interval of 9/8 may be built, akin to octave species scales built of two copies of a tetrachord (with a 9/8 remainder). The remaining 9/8 interval may be filled in a number of different ways. There are no 729-limit ABACABA scales with period 4/3, with steps > 20c. The list has an effective odd-limit of 675. | ||
| Line 1,852: | Line 1,829: | ||
|126/121 (~70.10c) | |126/121 (~70.10c) | ||
|1/1 22/21 12/11 8/7 7/6 11/9 14/11 4/3 | |1/1 22/21 12/11 8/7 7/6 11/9 14/11 4/3 | ||
| | |189 | ||
|- | |- | ||
|24/23 (~73.68c) | |24/23 (~73.68c) | ||
| Line 1,860: | Line 1,837: | ||
|} | |} | ||
=== Tetrachord to | === Tetrachord to 26/23 -> C = 529/507 (~73.54c)=== | ||
{| class="wikitable" | {| class="wikitable" | ||
|+ | |+ | ||
| Line 1,868: | Line 1,845: | ||
!odd-limit of scale intervals | !odd-limit of scale intervals | ||
|- | |- | ||
| | |24/23 (~73.68c) | ||
| | |299/288 (~64.89c) | ||
|1/1 | |1/1 24/23 13/12 26/23 46/39 16/13 23/18 4/3 | ||
| | |529 | ||
|} | |} | ||
=== Tetrachord to | === Tetrachord to 10/9 -> C = 27/25 (~133.24c) === | ||
{| class="wikitable" | {| class="wikitable" | ||
|+ | |+ | ||
| Line 1,882: | Line 1,859: | ||
!odd-limit of scale intervals | !odd-limit of scale intervals | ||
|- | |- | ||
|25/24 (~70.67c) | |||
|128/125 (~41.06c) | |||
|25/24 (~70.67c) | |||
|128/125 (~41.06c) | |||
|1/1 25/24 16/15 10/9 6/5 5/4 32/25 4/3 | |1/1 25/24 16/15 10/9 6/5 5/4 32/25 4/3 | ||
|625 | |625 | ||
|} | |} | ||
| Line 1,973: | Line 1,879: | ||
|} | |} | ||
{{Navbox scale gallery}} | |||
[[Category: Just intonation scales]] | [[Category: Just intonation scales]] | ||
[[Category: Step-nested scales]] | [[Category: Step-nested scales]] | ||
[[Category:Wakalixes]] | [[Category:Wakalixes]] | ||
[[Category:Lists of scales]] | [[Category:Lists of scales]] | ||