388edo: Difference between revisions
ArrowHead294 (talk | contribs) mNo edit summary |
Cleanup and update |
||
| Line 5: | Line 5: | ||
388edo is the first edo that is [[consistency|distinctly consistent]] through to the [[27-odd-limit]]; it is also consistent through the [[37-odd-limit]]. | 388edo is the first edo that is [[consistency|distinctly consistent]] through to the [[27-odd-limit]]; it is also consistent through the [[37-odd-limit]]. | ||
The equal temperament [[tempering out|tempers out]] the [[vishnuzma]], {{monzo| 23 6 -14 }}, the [[ | The equal temperament [[tempering out|tempers out]] the [[vishnuzma]], {{monzo| 23 6 -14 }}, the [[alphatricot comma]], {{monzo| 39 -29 3 }}, the [[minortone comma]], {{monzo| -16 35 -17 }}, and the [[Very high accuracy temperaments #Raider|raider comma]], {{monzo| 71 -99 31 }}, in the 5-limit, giving a strong tuning. It tempers out [[4375/4374]] and 235298/234375 in the 7-limit, and [[3025/3024]], [[5632/5625]] and [[9801/9800]] in the 11-limit and [[847/845]], [[1001/1000]] and [[4096/4095]] in the 13-limit. | ||
It provides the [[optimal patent val]] for the rank-5 cuthbert temperament, which tempers out [[847/845]], the cuthbert comma, and for a number of other temperaments tempering it out, e.g. [[neusec]], the {{nowrap|190 & | It provides the [[optimal patent val]] for the rank-5 cuthbert temperament, which tempers out [[847/845]], the cuthbert comma, and for a number of other temperaments tempering it out, e.g. [[neusec]], the {{nowrap| 190 & 198 }} temperament. By tempering out cuthbert it [[support]]s [[cuthbert chords]], in addition to [[sinbadmic chords]]. | ||
=== Prime harmonics === | === Prime harmonics === | ||
| Line 13: | Line 13: | ||
=== Subsets and supersets === | === Subsets and supersets === | ||
Since 388 factors into {{ | Since 388 factors into {{nowrap| 2<sup>2</sup> × 97 }}, 388edo has subset edos {{EDOs| 2, 4, 97, and 194 }}. | ||
== Regular temperament properties == | == Regular temperament properties == | ||
| Line 21: | Line 21: | ||
! rowspan="2" | [[Comma list]] | ! rowspan="2" | [[Comma list]] | ||
! rowspan="2" | [[Mapping]] | ! rowspan="2" | [[Mapping]] | ||
! rowspan="2" | Optimal<br | ! rowspan="2" | Optimal<br>8ve stretch (¢) | ||
! colspan="2" | Tuning error | ! colspan="2" | Tuning error | ||
|- | |- | ||
| Line 28: | Line 28: | ||
|- | |- | ||
| 2.3 | | 2.3 | ||
| {{ | | {{Monzo| 615 -388 }} | ||
| {{ | | {{Mapping| 388 615 }} | ||
| +0.0337 | | +0.0337 | ||
| 0.0337 | | 0.0337 | ||
| Line 35: | Line 35: | ||
|- | |- | ||
| 2.3.5 | | 2.3.5 | ||
| {{ | | {{Monzo| 23 6 -14 }}, {{monzo| 39 -29 3 }} | ||
| {{ | | {{Mapping| 388 615 901 }} | ||
| −0.0633 | | −0.0633 | ||
| 0.0501 | | 0.0501 | ||
| Line 43: | Line 43: | ||
| 2.3.5.7 | | 2.3.5.7 | ||
| 4375/4374, 235298/234375, 2100875/2097152 | | 4375/4374, 235298/234375, 2100875/2097152 | ||
| {{ | | {{Mapping| 388 615 901 1089 }} | ||
| +0.0224 | | +0.0224 | ||
| 0.1546 | | 0.1546 | ||
| Line 50: | Line 50: | ||
| 2.3.5.7.11 | | 2.3.5.7.11 | ||
| 3025/3024, 4375/4374, 5632/5625, 235298/234375 | | 3025/3024, 4375/4374, 5632/5625, 235298/234375 | ||
| {{ | | {{Mapping| 388 615 901 1089 1342 }} | ||
| +0.0643 | | +0.0643 | ||
| 0.1617 | | 0.1617 | ||
| Line 57: | Line 57: | ||
| 2.3.5.7.11.13 | | 2.3.5.7.11.13 | ||
| 847/845, 1001/1000, 3025/3024, 4096/4095, 4375/4374 | | 847/845, 1001/1000, 3025/3024, 4096/4095, 4375/4374 | ||
| {{ | | {{Mapping| 388 615 901 1089 1342 1436 }} | ||
| +0.0216 | | +0.0216 | ||
| 0.1758 | | 0.1758 | ||
| Line 64: | Line 64: | ||
| 2.3.5.7.11.13.17 | | 2.3.5.7.11.13.17 | ||
| 833/832, 847/845, 1001/1000, 1089/1088, 1225/1224, 1701/1700 | | 833/832, 847/845, 1001/1000, 1089/1088, 1225/1224, 1701/1700 | ||
| {{ | | {{Mapping| 388 615 901 1089 1342 1436 1586 }} | ||
| +0.0116 | | +0.0116 | ||
| 0.1646 | | 0.1646 | ||
| Line 71: | Line 71: | ||
| 2.3.5.7.11.13.17.19 | | 2.3.5.7.11.13.17.19 | ||
| 833/832, 847/845, 1001/1000, 1089/1088, 1216/1215, 1225/1224, 1331/1330 | | 833/832, 847/845, 1001/1000, 1089/1088, 1216/1215, 1225/1224, 1331/1330 | ||
| {{ | | {{Mapping| 388 615 901 1089 1342 1436 1586 1648 }} | ||
| +0.0280 | | +0.0280 | ||
| 0.1600 | | 0.1600 | ||
| Line 82: | Line 82: | ||
|+ style="font-size: 105%;" | Table of rank-2 temperaments by generator | |+ style="font-size: 105%;" | Table of rank-2 temperaments by generator | ||
|- | |- | ||
! Periods<br | ! Periods<br>per 8ve | ||
! Generator* | ! Generator* | ||
! Cents* | ! Cents* | ||
! Associated<br | ! Associated<br>ratio* | ||
! Temperaments | ! Temperaments | ||
|- | |- | ||
| Line 110: | Line 110: | ||
| 565.97 | | 565.97 | ||
| 75/52 | | 75/52 | ||
| [[ | | [[Alphatrillium]] / [[pseudotrillium]] | ||
|- | |- | ||
| 2 | | 2 | ||
| Line 125: | Line 125: | ||
|- | |- | ||
| 4 | | 4 | ||
| 123\388<br | | 123\388<br>(26\388) | ||
| 380.41<br | | 380.41<br>(80.41) | ||
| 81/65<br | | 81/65<br>(22/21) | ||
| [[Quasithird]] | | [[Quasithird]] | ||
|- | |- | ||
| 97 | | 97 | ||
| 161\388<br | | 161\388<br>(1\388) | ||
| 497.938<br | | 497.938<br>(3.09) | ||
| 4/3<br | | 4/3<br>(?) | ||
| [[Berkelium]] | | [[Berkelium]] | ||
|} | |} | ||
<nowiki />* [[Normal lists|Octave-reduced form]], reduced to the first half-octave, and [[Normal lists|minimal form]] in parentheses if distinct | <nowiki/>* [[Normal lists|Octave-reduced form]], reduced to the first half-octave, and [[Normal lists|minimal form]] in parentheses if distinct | ||
[[Category:Cuthbert]] | [[Category:Cuthbert]] | ||
Revision as of 15:07, 16 March 2025
| ← 387edo | 388edo | 389edo → |
388 equal divisions of the octave (abbreviated 388edo or 388ed2), also called 388-tone equal temperament (388tet) or 388 equal temperament (388et) when viewed under a regular temperament perspective, is the tuning system that divides the octave into 388 equal parts of about 3.09 ¢ each. Each step represents a frequency ratio of 21/388, or the 388th root of 2.
Theory
388edo is the first edo that is distinctly consistent through to the 27-odd-limit; it is also consistent through the 37-odd-limit.
The equal temperament tempers out the vishnuzma, [23 6 -14⟩, the alphatricot comma, [39 -29 3⟩, the minortone comma, [-16 35 -17⟩, and the raider comma, [71 -99 31⟩, in the 5-limit, giving a strong tuning. It tempers out 4375/4374 and 235298/234375 in the 7-limit, and 3025/3024, 5632/5625 and 9801/9800 in the 11-limit and 847/845, 1001/1000 and 4096/4095 in the 13-limit.
It provides the optimal patent val for the rank-5 cuthbert temperament, which tempers out 847/845, the cuthbert comma, and for a number of other temperaments tempering it out, e.g. neusec, the 190 & 198 temperament. By tempering out cuthbert it supports cuthbert chords, in addition to sinbadmic chords.
Prime harmonics
| Harmonic | 2 | 3 | 5 | 7 | 11 | 13 | 17 | 19 | 23 | 29 | 31 | 37 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Error | Absolute (¢) | +0.00 | +0.11 | +0.28 | -0.78 | -0.80 | +0.71 | +0.20 | -0.61 | -0.44 | +0.32 | -0.71 | -0.83 |
| Relative (%) | +0.0 | +3.5 | +9.2 | -25.4 | -25.9 | +22.9 | +6.4 | -19.6 | -14.2 | +10.3 | -22.8 | -26.8 | |
| Steps (reduced) |
388 (0) |
615 (227) |
901 (125) |
1089 (313) |
1342 (178) |
1436 (272) |
1586 (34) |
1648 (96) |
1755 (203) |
1885 (333) |
1922 (370) |
2021 (81) | |
Subsets and supersets
Since 388 factors into 22 × 97, 388edo has subset edos 2, 4, 97, and 194.
Regular temperament properties
| Subgroup | Comma list | Mapping | Optimal 8ve stretch (¢) |
Tuning error | |
|---|---|---|---|---|---|
| Absolute (¢) | Relative (%) | ||||
| 2.3 | [615 -388⟩ | [⟨388 615]] | +0.0337 | 0.0337 | 1.09 |
| 2.3.5 | [23 6 -14⟩, [39 -29 3⟩ | [⟨388 615 901]] | −0.0633 | 0.0501 | 1.62 |
| 2.3.5.7 | 4375/4374, 235298/234375, 2100875/2097152 | [⟨388 615 901 1089]] | +0.0224 | 0.1546 | 5.00 |
| 2.3.5.7.11 | 3025/3024, 4375/4374, 5632/5625, 235298/234375 | [⟨388 615 901 1089 1342]] | +0.0643 | 0.1617 | 5.23 |
| 2.3.5.7.11.13 | 847/845, 1001/1000, 3025/3024, 4096/4095, 4375/4374 | [⟨388 615 901 1089 1342 1436]] | +0.0216 | 0.1758 | 5.68 |
| 2.3.5.7.11.13.17 | 833/832, 847/845, 1001/1000, 1089/1088, 1225/1224, 1701/1700 | [⟨388 615 901 1089 1342 1436 1586]] | +0.0116 | 0.1646 | 5.32 |
| 2.3.5.7.11.13.17.19 | 833/832, 847/845, 1001/1000, 1089/1088, 1216/1215, 1225/1224, 1331/1330 | [⟨388 615 901 1089 1342 1436 1586 1648]] | +0.0280 | 0.1600 | 5.17 |
- 388et has a lower absolute error in the 5-limit than any previous equal temperaments, past 323 and followed by 441.
Rank-2 temperaments
| Periods per 8ve |
Generator* | Cents* | Associated ratio* |
Temperaments |
|---|---|---|---|---|
| 1 | 59\388 | 182.47 | 10/9 | Mitonic |
| 1 | 111\388 | 343.30 | 8000/6561 | Raider |
| 1 | 145\388 | 448.45 | 35/27 | Semidimfourth |
| 1 | 183\388 | 565.97 | 75/52 | Alphatrillium / pseudotrillium |
| 2 | 23\388 | 71.13 | 25/24 | Vishnu / ananta |
| 2 | 49\388 | 151.54 | 12/11 | Neusec |
| 4 | 123\388 (26\388) |
380.41 (80.41) |
81/65 (22/21) |
Quasithird |
| 97 | 161\388 (1\388) |
497.938 (3.09) |
4/3 (?) |
Berkelium |
* Octave-reduced form, reduced to the first half-octave, and minimal form in parentheses if distinct