248edo: Difference between revisions
+RTT table and rank-2 temperaments |
m Text replacement - "[[Helmholtz temperament|" to "[[Helmholtz (temperament)|" |
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{{ | {{Infobox ET}} | ||
{{ED intro}} | |||
== Theory == | == Theory == | ||
248edo shares the mapping of [[harmonic]]s [[5/1|5]] and [[7/1|7]] with [[31edo]]. It has a decent 13-limit interpretation despite not being [[consistent]]. The equal temperament [[tempering out|tempers out]] [[32805/32768]] in the 5-limit; [[3136/3125]] and [[420175/419904]] in the 7-limit; [[441/440]], [[8019/8000]] in the 11-limit; [[729/728]], [[847/845]], [[1001/1000]], [[1575/1573]] and [[2200/2197]] in the 13-limit. It also notably tempers out the [[quartisma]]. 248edo, additionally, has the interesting property of its mapping for all prime harmonics 3 to 23 being a multiple of 3, and therefore derived from [[131edt]]. Similarly, using the lower-error 248[[Wart notation|h]] val, the mappings of all its [[2.5.7_subgroup|no-3]] harmonics up to [[23-limit|28]] are multiples of 2 and derived from [[124edo]]. | |||
It [[support]]s [[ | It [[support]]s the [[bischismic]] temperament, providing the [[optimal patent val]] for 11-limit bischismic, and excellent tunings in the 7- and 13-limits. It also provides the optimal patent val for the [[essence]] temperament. It is notable for its combination of precise intonation with an abundance of essentially tempered chords. | ||
=== Prime harmonics === | === Prime harmonics === | ||
{{Harmonics in equal|248|}} | {{Harmonics in equal|248|}} | ||
=== Subsets and supersets === | |||
Since 248 factors into {{factorization|248}}, 248edo has subset edos {{EDOs| 2, 4, 8, 31, 62, and 124 }}. | |||
== 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 22: | Line 27: | ||
| 2.3 | | 2.3 | ||
| {{monzo| 287 -181 }} | | {{monzo| 287 -181 }} | ||
| | | {{mapping| 248 393 }} | ||
| +0.108 | | +0.108 | ||
| 0.108 | | 0.108 | ||
Line 29: | Line 34: | ||
| 2.3.5 | | 2.3.5 | ||
| 32805/32768, {{monzo| 12 32 -27 }} | | 32805/32768, {{monzo| 12 32 -27 }} | ||
| | | {{mapping| 248 393 576 }} | ||
| -0.041 | | -0.041 | ||
| 0.228 | | 0.228 | ||
Line 36: | Line 41: | ||
| 2.3.5.7 | | 2.3.5.7 | ||
| 3136/3125, 32805/32768, 420175/419904 | | 3136/3125, 32805/32768, 420175/419904 | ||
| | | {{mapping| 248 393 576 696 }} | ||
| +0.066 | | +0.066 | ||
| 0.270 | | 0.270 | ||
Line 43: | Line 48: | ||
| 2.3.5.7.11 | | 2.3.5.7.11 | ||
| 441/440, 3136/3125, 8019/8000, 41503/41472 | | 441/440, 3136/3125, 8019/8000, 41503/41472 | ||
| | | {{mapping| 248 393 576 696 858 }} | ||
| +0.036 | | +0.036 | ||
| 0.249 | | 0.249 | ||
Line 50: | Line 55: | ||
| 2.3.5.7.11.13 | | 2.3.5.7.11.13 | ||
| 441/440, 729/728, 847/845, 1001/1000, 3136/3125 | | 441/440, 729/728, 847/845, 1001/1000, 3136/3125 | ||
| | | {{mapping| 248 393 576 696 858 918 }} | ||
| +0.079 | | +0.079 | ||
| 0.275 | | 0.275 | ||
Line 58: | Line 63: | ||
=== 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* | |||
! Temperaments | ! Temperaments | ||
|- | |- | ||
Line 75: | Line 81: | ||
| 498.39 | | 498.39 | ||
| 4/3 | | 4/3 | ||
| [[Helmholtz]] | | [[Helmholtz (temperament)|Helmholtz]] | ||
|- | |- | ||
| 2 | | 2 | ||
| 77\248<br>(47\248) | | 77\248<br />(47\248) | ||
| 372.58<br>(227.42) | | 372.58<br />(227.42) | ||
| 26/21<br>(154/135) | | 26/21<br />(154/135) | ||
| [[Essence]] | | [[Essence]] | ||
|- | |- | ||
Line 90: | Line 96: | ||
|- | |- | ||
| 8 | | 8 | ||
| 117\248<br>(7\248) | | 117\248<br />(7\248) | ||
| 566.13<br>(33.87) | | 566.13<br />(33.87) | ||
| 104/75<br>(49/48) | | 104/75<br />(49/48) | ||
| [[Octowerck]] | | [[Octowerck]] | ||
|- | |- | ||
| 31 | | 31 | ||
| 103\248<br>(1\248) | | 103\248<br />(1\248) | ||
| 498.39<br>(4.84) | | 498.39<br />(4.84) | ||
| 4/3<br>(385/384) | | 4/3<br />(385/384) | ||
| [[Birds]] | | [[Birds]] | ||
|} | |} | ||
<nowiki />* [[Normal lists|Octave-reduced form]], reduced to the first half-octave, and [[Normal lists|minimal form]] in parentheses if distinct | |||
[[Category:Bischismic]] | [[Category:Bischismic]] | ||
[[Category:Essence]] | [[Category:Essence]] | ||