121edo: Difference between revisions
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121 isn't consistent in the 21-odd-limit, hence the table shows odd harmonics as per the template doc |
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{{Infobox ET}} | {{Infobox ET}} | ||
{{ED intro}} | |||
== Theory == | == Theory == | ||
121edo has a distinctly sharp tendency, in that the odd [[harmonic]]s from 3 to 19 all have sharp tunings. It [[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 [[ | 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. | ||
=== | === Odd harmonics === | ||
{{ | {{Harmonics in equal|121}} | ||
=== Subsets and supersets === | |||
Since 121 factors into 11<sup>2</sup>, 121edo contains [[11edo]] as its only nontrivial subset. | |||
== Regular temperament properties == | == Regular temperament properties == | ||
{| class="wikitable center-4 center-5 center-6" | {| class="wikitable center-4 center-5 center-6" | ||
! rowspan="2" | Subgroup | |- | ||
! rowspan="2" | [[Subgroup]] | |||
! rowspan="2" | [[Comma list]] | ! rowspan="2" | [[Comma list]] | ||
! rowspan="2" | [[Mapping]] | ! rowspan="2" | [[Mapping]] | ||
! rowspan="2" | Optimal<br>8ve stretch (¢) | ! rowspan="2" | Optimal<br />8ve stretch (¢) | ||
! colspan="2" | Tuning error | ! colspan="2" | Tuning error | ||
|- | |- | ||
Line 23: | Line 27: | ||
| 2.3 | | 2.3 | ||
| {{monzo| 192 -121 }} | | {{monzo| 192 -121 }} | ||
| | | {{mapping| 121 192 }} | ||
| | | −0.687 | ||
| 0.687 | | 0.687 | ||
| 6.93 | | 6.93 | ||
Line 30: | Line 34: | ||
| 2.3.5 | | 2.3.5 | ||
| 15625/15552, {{monzo| 31 -21 1 }} | | 15625/15552, {{monzo| 31 -21 1 }} | ||
| | | {{mapping| 121 192 281 }} | ||
| | | −0.524 | ||
| 0.606 | | 0.606 | ||
| 6.11 | | 6.11 | ||
Line 37: | Line 41: | ||
| 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 | ||
| 0.580 | | 0.580 | ||
| 5.85 | | 5.85 | ||
Line 44: | Line 48: | ||
| 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 | ||
| 0.556 | | 0.556 | ||
| 5.61 | | 5.61 | ||
Line 51: | Line 55: | ||
| 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 | ||
| 0.510 | | 0.510 | ||
| 5.14 | | 5.14 | ||
Line 58: | Line 62: | ||
| 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 | ||
| 0.480 | | 0.480 | ||
| 4.85 | | 4.85 | ||
Line 65: | Line 69: | ||
| 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 | ||
| 0.519 | | 0.519 | ||
| 5.23 | | 5.23 | ||
|} | |} | ||
* 121et (121i val) has lower absolute errors than any previous equal temperaments in the 13-, 17-, 19-, and 23-limit, beating [[111edo|111]] before being superseded by [[130edo|130]] in all those limits except for the 17-limit, where it is superseded by [[140edo|140]]. | |||
=== Rank-2 temperaments === | === Rank-2 temperaments === | ||
{| class="wikitable center-all left-5" | {| class="wikitable center-all left-5" | ||
|+Table of rank-2 temperaments by generator | |+ style="font-size: 105%;" | Table of rank-2 temperaments by generator | ||
! Periods<br>per | |- | ||
! Generator | ! Periods<br />per 8ve | ||
! Cents | ! Generator* | ||
! Associated<br>ratio | ! Cents* | ||
! | ! Associated<br />ratio* | ||
! Temperament | |||
|- | |- | ||
| 1 | | 1 | ||
Line 120: | Line 126: | ||
| 317.36 | | 317.36 | ||
| 6/5 | | 6/5 | ||
| [[ | | [[Metakleismic]] | ||
|- | |- | ||
| 1 | | 1 | ||
Line 183: | Line 189: | ||
|- | |- | ||
| 11 | | 11 | ||
| 50\121<br>(5\121) | | 50\121<br />(5\121) | ||
| 495.87<br>(49.59) | | 495.87<br />(49.59) | ||
| 4/3<br>(36/35) | | 4/3<br />(36/35) | ||
| [[Hendecatonic]] | | [[Hendecatonic]] | ||
|} | |} | ||
<nowiki />* [[Normal lists|Octave-reduced form]], reduced to the first half-octave, and [[Normal lists|minimal form]] in parentheses if distinct | |||
== 13-limit detempering of | == 13-limit detempering of 121et == | ||
{{See also| Detempering }} | {{See also| Detempering }} | ||
[100/99, 64/63, 50/49, 40/39, 36/35, 28/27, 25/24, 22/21, 21/20, 35/33, 16/15, 15/14, 14/13, 13/12, 12/11, 35/32, 11/10, 10/9, 39/35, 28/25, 9/8, 25/22, 8/7, 55/48, 15/13, 64/55, 7/6, 75/64, 13/11, 25/21, 105/88, 6/5, 63/52, 40/33, 11/9, 16/13, 26/21, 56/45, 5/4, 44/35, 63/50, 14/11, 32/25, 9/7, 35/27, 13/10, 55/42, 21/16, 33/25, 4/3, 75/56, 35/26, 27/20, 15/11, 48/35, 11/8, 18/13, 39/28, 7/5, 45/32, 64/45, 10/7, 56/39, 13/9, 16/11, 35/24, 22/15, 40/27, 49/33, 112/75, 3/2, 50/33, 32/21, 55/36, 20/13, 54/35, 14/9, 25/16, 11/7, 63/40, 35/22, 8/5, 45/28, 21/13, 13/8, 18/11, 33/20, 104/63, 5/3, 117/70, 42/25, 22/13, 75/44, 12/7, 55/32, 26/15, 96/55, 7/4, 44/25, 16/9, 25/14, 70/39, 9/5, 20/11, 64/35, 11/6, 24/13, 13/7, 28/15, 15/8, 49/26, 40/21, 21/11, 25/13, 27/14, 35/18, 39/20, 49/25, 63/32, 99/50, 2] | [100/99, 64/63, 50/49, 40/39, 36/35, 28/27, 25/24, 22/21, 21/20, 35/33, 16/15, 15/14, 14/13, 13/12, 12/11, 35/32, 11/10, 10/9, 39/35, 28/25, 9/8, 25/22, 8/7, 55/48, 15/13, 64/55, 7/6, 75/64, 13/11, 25/21, 105/88, 6/5, 63/52, 40/33, 11/9, 16/13, 26/21, 56/45, 5/4, 44/35, 63/50, 14/11, 32/25, 9/7, 35/27, 13/10, 55/42, 21/16, 33/25, 4/3, 75/56, 35/26, 27/20, 15/11, 48/35, 11/8, 18/13, 39/28, 7/5, 45/32, 64/45, 10/7, 56/39, 13/9, 16/11, 35/24, 22/15, 40/27, 49/33, 112/75, 3/2, 50/33, 32/21, 55/36, 20/13, 54/35, 14/9, 25/16, 11/7, 63/40, 35/22, 8/5, 45/28, 21/13, 13/8, 18/11, 33/20, 104/63, 5/3, 117/70, 42/25, 22/13, 75/44, 12/7, 55/32, 26/15, 96/55, 7/4, 44/25, 16/9, 25/14, 70/39, 9/5, 20/11, 64/35, 11/6, 24/13, 13/7, 28/15, 15/8, 49/26, 40/21, 21/11, 25/13, 27/14, 35/18, 39/20, 49/25, 63/32, 99/50, 2] | ||
==Miscellany== | == Miscellany == | ||
Since 121 is part of the Fibonacci sequence beginning with 5 and 12, 121edo closely approximates [[peppermint]] temperament. This makes it suitable for [[neo-Gothic]] tunings. | |||
Since 121 is part of the Fibonacci sequence beginning with 5 and 12, 121edo closely approximates peppermint temperament. This makes it suitable for neo-Gothic tunings. | |||
[[Category:Grendel]] | [[Category:Grendel]] | ||
[[Category:Quintupole]] | [[Category:Quintupole]] | ||