121edo: Difference between revisions

BudjarnLambeth (talk | contribs)
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 primes from 3 to 19 all have sharp tunings. It tempers out [[15625/15552]] 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]].
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 }}
| [{{val| 121 192 }}]
| {{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 }}
| [{{val| 121 192 281 }}]
| {{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
| [{{val| 121 192 281 340 }}]
| {{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
| [{{val| 121 192 281 340 419 }}]
| {{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
| [{{val| 121 192 281 340 419 448 }}]
| {{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
| [{{val| 121 192 281 340 419 448 495 }}]
| {{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
| [{{val| 121 192 281 340 419 448 495 514 }}]
| {{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<br>(Reduced)
! Generator*
! Cents<br>(Reduced)
! 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 ==