121edo: Difference between revisions
→Miscellany: Added links to peppermint and neo-Gothic |
Cleanup |
||
Line 3: | Line 3: | ||
== Theory == | == Theory == | ||
121edo has a distinctly sharp tendency, in that the odd | 121edo has a distinctly sharp tendency, in that the odd [[harmonic]]s from 3 to 19 all have sharp tunings. The equal temperament [[tempering out|tempers out]] 15625/15552 ([[15625/15552|kleisma]]) in the [[5-limit]]; [[4000/3969]], [[6144/6125]], [[10976/10935]] in the [[7-limit]]; [[540/539]], [[896/891]] and [[1375/1372]] in the 11-limit; [[325/324]], [[352/351]], [[364/363]] and [[625/624]] in the [[13-limit]]; [[256/255]], [[375/374]] and [[442/441]] in the [[17-limit]]; [[190/189]] and [[361/360]] in the [[19-limit]]. It also serves as the [[optimal patent val]] for 13-limit [[grendel]] temperament. It is [[consistent]] through to the [[19-odd-limit]] and uniquely consistent to the [[15-odd-limit]]. | ||
Because it tempers out 540/539 it allows [[swetismic chords]], because it tempers out 325/324 it allows [[marveltwin chords]], because it tempers out 640/637 it allows [[huntmic chords]], because it tempers out 352/351 it allows [[major minthmic chords]], because it tempers out 364/363 it allows [[minor minthmic chords]], because it tempers out 676/675 it allows [[island chords]] and because it tempers out 1575/1573 it allows [[nicolic chords]]. That makes for a very flexible system, and since this suite of commas defines 13-limit 121et, it is a system only associated with 121. | Because it tempers out 540/539 it allows [[swetismic chords]], because it tempers out 325/324 it allows [[marveltwin chords]], because it tempers out 640/637 it allows [[huntmic chords]], because it tempers out 352/351 it allows [[major minthmic chords]], because it tempers out 364/363 it allows [[minor minthmic chords]], because it tempers out 676/675 it allows [[island chords]] and because it tempers out 1575/1573 it allows [[nicolic chords]]. That makes for a very flexible system, and since this suite of commas defines 13-limit 121et, it is a system only associated with 121. | ||
Line 23: | Line 23: | ||
| 2.3 | | 2.3 | ||
| {{monzo| 192 -121 }} | | {{monzo| 192 -121 }} | ||
| | | {{mapping| 121 192 }} | ||
| -0.687 | | -0.687 | ||
| 0.687 | | 0.687 | ||
Line 30: | Line 30: | ||
| 2.3.5 | | 2.3.5 | ||
| 15625/15552, {{monzo| 31 -21 1 }} | | 15625/15552, {{monzo| 31 -21 1 }} | ||
| | | {{mapping| 121 192 281 }} | ||
| -0.524 | | -0.524 | ||
| 0.606 | | 0.606 | ||
Line 37: | Line 37: | ||
| 2.3.5.7 | | 2.3.5.7 | ||
| 4000/3969, 6144/6125, 10976/10935 | | 4000/3969, 6144/6125, 10976/10935 | ||
| | | {{mapping| 121 192 281 340 }} | ||
| -0.667 | | -0.667 | ||
| 0.580 | | 0.580 | ||
Line 44: | Line 44: | ||
| 2.3.5.7.11 | | 2.3.5.7.11 | ||
| 540/539, 896/891, 1375/1372, 4375/4356 | | 540/539, 896/891, 1375/1372, 4375/4356 | ||
| | | {{mapping| 121 192 281 340 419 }} | ||
| -0.768 | | -0.768 | ||
| 0.556 | | 0.556 | ||
Line 51: | Line 51: | ||
| 2.3.5.7.11.13 | | 2.3.5.7.11.13 | ||
| 325/324, 352/351, 364/363, 540/539, 625/624 | | 325/324, 352/351, 364/363, 540/539, 625/624 | ||
| | | {{mapping| 121 192 281 340 419 448 }} | ||
| -0.750 | | -0.750 | ||
| 0.510 | | 0.510 | ||
Line 58: | Line 58: | ||
| 2.3.5.7.11.13.17 | | 2.3.5.7.11.13.17 | ||
| 256/255, 325/324, 352/351, 364/363, 375/374, 442/441 | | 256/255, 325/324, 352/351, 364/363, 375/374, 442/441 | ||
| | | {{mapping| 121 192 281 340 419 448 495 }} | ||
| -0.787 | | -0.787 | ||
| 0.480 | | 0.480 | ||
Line 65: | Line 65: | ||
| 2.3.5.7.11.13.17.19 | | 2.3.5.7.11.13.17.19 | ||
| 190/189, 256/255, 325/324, 352/351, 361/360, 364/363, 375/374 | | 190/189, 256/255, 325/324, 352/351, 361/360, 364/363, 375/374 | ||
| | | {{mapping| 121 192 281 340 419 448 495 514 }} | ||
| -0.689 | | -0.689 | ||
| 0.519 | | 0.519 | ||
Line 75: | Line 75: | ||
|+Table of rank-2 temperaments by generator | |+Table of rank-2 temperaments by generator | ||
! Periods<br>per 8ve | ! Periods<br>per 8ve | ||
! Generator | ! Generator* | ||
! Cents | ! Cents* | ||
! Associated<br>Ratio | ! Associated<br>Ratio* | ||
! Temperaments | ! Temperaments | ||
|- | |- | ||
Line 188: | Line 188: | ||
| [[Hendecatonic]] | | [[Hendecatonic]] | ||
|} | |} | ||
<nowiki>*</nowiki> [[Normal lists|octave-reduced form]], reduced to the first half-octave, and [[Normal lists|minimal form]] in parentheses if it is distinct | |||
== 13-limit detempering of 121et == | == 13-limit detempering of 121et == |