38edo: Difference between revisions
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{{Infobox ET}} | {{Infobox ET}} | ||
{{ | {{ED intro}} | ||
== Theory == | == Theory == | ||
Since {{nowrap|38 {{=}} 2 | Since {{nowrap|38 {{=}} 2 × 19}}, it can be thought of as two parallel [[19edo]]s. While the halving of the step size lowers [[consistency]] and leaves it only mediocre in terms of overall [[relative interval error|relative error]], the fact that the 3rd and 5th harmonics are flat by almost exactly the same amount, while the 11th is double that means there are quite a few near perfect composite ratios, such as the the [[6/5]] it shares with 19edo, plus [[11/9]], [[15/11]] & [[25/22]], (and their inversions) while a single step nears [[55/54]]; the approximation to [[11/9]] in particular should be noted for forming a 10-strong [[consistent circle]]. This gives several interesting possibilities for unusual near-just chords such as 15:18:22:25:30. | ||
It [[tempering out|tempers out]] the same [[5-limit]] commas as 19edo, namely [[81/80]], [[3125/3072]] and [[15625/15552]]. In the [[7-limit]], we can add [[50/49]], and tempering out 81/80 and 50/49 gives [[injera]] temperament, for which 38 is the [[optimal patent val]]. In the [[11-limit]], we can add 121/120 and 176/175. | |||
The harmonic series from 1 to 20 is approximated within 38df by the sequence: {{nowrap|38 22 16 12 10 8 8 6 6 5 5 4 4 4 4 3 3 3 3}} | Using the [[Warts|38df]] mapping, every [[prime interval]] from 3 to 19 is characterized by a flat intonation. Furthermore, the [[mapping]] of all [[19-odd-limit]] intervals in 38df aligns with their closest approximations in 38edo, excepting for 7/4 and 13/8, along with their octave complements 8/7 and 16/13, which are by definition mapped to their secondary optimal steps within 38df. In other words, all 19-odd-limit intervals are [[consistency|consistent]] within the 38df [[val]] {{val| 38 60 88 106 131 140 155 161 }}. | ||
The harmonic series from 1 to 20 is approximated within 38df by the sequence: {{nowrap| 38 22 16 12 10 8 8 6 6 5 5 4 4 4 4 3 3 3 3 }} | |||
[[File:Harmonic_series_38df.mp3]] [[:File:Harmonic_series_38df.mp3|[Harmonic series 2-20 in 38df]]] | [[File:Harmonic_series_38df.mp3]] [[:File:Harmonic_series_38df.mp3|[Harmonic series 2-20 in 38df]]] | ||
=== Prime harmonics === | |||
{{Harmonics in equal|38}} | {{Harmonics in equal|38}} | ||
Line 18: | Line 21: | ||
! Step | ! Step | ||
! Cents | ! Cents | ||
! 19-odd-limit ratios,<br | ! 19-odd-limit ratios,<br>in 38df val | ||
! colspan="3" | [[Ups and | ! colspan="3" | [[Ups and downs notation]]* | ||
([[Enharmonic unisons in ups and downs notation|EUs]]: vvA1 and vvd2) | |||
|- | |- | ||
| 0 | | 0 | ||
| 0. | | 0.0 | ||
| | | | ||
| Perfect 1sn | | Perfect 1sn | ||
Line 29: | Line 33: | ||
|- | |- | ||
| 1 | | 1 | ||
| 31. | | 31.6 | ||
| | | | ||
| Up 1sn | | Up 1sn | ||
Line 36: | Line 40: | ||
|- | |- | ||
| 2 | | 2 | ||
| 63. | | 63.2 | ||
| | | | ||
| Aug 1sn, dim 2nd | | Aug 1sn, dim 2nd | ||
Line 43: | Line 47: | ||
|- | |- | ||
| 3 | | 3 | ||
| 94. | | 94.7 | ||
| [[20/19]], [[19/18]], [[18/17]], [[17/16]] | | [[20/19]], [[19/18]], [[18/17]], [[17/16]] | ||
| Upaug 1sn, downminor 2nd | | Upaug 1sn, downminor 2nd | ||
Line 50: | Line 54: | ||
|- | |- | ||
| 4 | | 4 | ||
| 126. | | 126.3 | ||
| [[16/15]], [[15/14]], [[14/13]], [[13/12]] | | [[16/15]], [[15/14]], [[14/13]], [[13/12]] | ||
| Minor 2nd | | Minor 2nd | ||
Line 57: | Line 61: | ||
|- | |- | ||
| 5 | | 5 | ||
| 157. | | 157.9 | ||
| [[12/11]], [[11/10]] | | [[12/11]], [[11/10]] | ||
| Mid 2nd | | Mid 2nd | ||
Line 64: | Line 68: | ||
|- | |- | ||
| 6 | | 6 | ||
| 189. | | 189.5 | ||
| [[10/9]], [[19/17]], [[9/8]] | | [[10/9]], [[19/17]], [[9/8]] | ||
| Major 2nd | | Major 2nd | ||
Line 71: | Line 75: | ||
|- | |- | ||
| 7 | | 7 | ||
| 221. | | 221.1 | ||
| [[17/15]] | | [[17/15]] | ||
| Upmajor 2nd | | Upmajor 2nd | ||
Line 78: | Line 82: | ||
|- | |- | ||
| 8 | | 8 | ||
| 252. | | 252.6 | ||
| [[8/7]], [[15/13]], [[22/19]], [[7/6]] | | [[8/7]], [[15/13]], [[22/19]], [[7/6]] | ||
| Aug 2nd, Dim 3rd | | Aug 2nd, Dim 3rd | ||
Line 85: | Line 89: | ||
|- | |- | ||
| 9 | | 9 | ||
| 284. | | 284.2 | ||
| [[20/17]], [[13/11]], [[19/16]] | | [[20/17]], [[13/11]], [[19/16]] | ||
| Downminor 3rd | | Downminor 3rd | ||
Line 92: | Line 96: | ||
|- | |- | ||
| 10 | | 10 | ||
| 315. | | 315.8 | ||
| [[6/5]] | | [[6/5]] | ||
| Minor 3rd | | Minor 3rd | ||
Line 99: | Line 103: | ||
|- | |- | ||
| 11 | | 11 | ||
| 347. | | 347.4 | ||
| [[17/14]], [[11/9]] | | [[17/14]], [[11/9]] | ||
| Mid 3rd | | Mid 3rd | ||
Line 106: | Line 110: | ||
|- | |- | ||
| 12 | | 12 | ||
| 378. | | 378.9 | ||
| [[16/13]], [[5/4]] | | [[16/13]], [[5/4]] | ||
| Major 3rd | | Major 3rd | ||
Line 113: | Line 117: | ||
|- | |- | ||
| 13 | | 13 | ||
| 410. | | 410.5 | ||
| [[24/19]], [[19/15]], [[14/11]] | | [[24/19]], [[19/15]], [[14/11]] | ||
| Upmajor 3rd, Downdim 4th | | Upmajor 3rd, Downdim 4th | ||
Line 120: | Line 124: | ||
|- | |- | ||
| 14 | | 14 | ||
| 442. | | 442.1 | ||
| [[9/7]], [[22/17]], [[13/10]] | | [[9/7]], [[22/17]], [[13/10]] | ||
| Aug 3rd, dim 4th | | Aug 3rd, dim 4th | ||
Line 127: | Line 131: | ||
|- | |- | ||
| 15 | | 15 | ||
| 473. | | 473.7 | ||
| [[17/13]] | | [[17/13]] | ||
| Down 4th | | Down 4th | ||
Line 134: | Line 138: | ||
|- | |- | ||
| 16 | | 16 | ||
| 505. | | 505.3 | ||
| [[4/3]] | | [[4/3]] | ||
| Perfect 4th | | Perfect 4th | ||
Line 141: | Line 145: | ||
|- | |- | ||
| 17 | | 17 | ||
| 536. | | 536.8 | ||
| [[19/14]], [[15/11]], [[26/19]], [[11/8]] | | [[19/14]], [[15/11]], [[26/19]], [[11/8]] | ||
| Up 4th | | Up 4th | ||
Line 148: | Line 152: | ||
|- | |- | ||
| 18 | | 18 | ||
| 568. | | 568.4 | ||
| [[18/13]], [[7/5]] | | [[18/13]], [[7/5]] | ||
| Aug 4th | | Aug 4th | ||
Line 155: | Line 159: | ||
|- | |- | ||
| 19 | | 19 | ||
| 600. | | 600.0 | ||
| [[24/17]], [[17/12]] | | [[24/17]], [[17/12]] | ||
| Upaug 4th, downdim 5th | | Upaug 4th, downdim 5th | ||
Line 162: | Line 166: | ||
|- | |- | ||
| 20 | | 20 | ||
| 631. | | 631.6 | ||
| [[10/7]], [[13/9]] | | [[10/7]], [[13/9]] | ||
| Dim 5th | | Dim 5th | ||
Line 169: | Line 173: | ||
|- | |- | ||
| 21 | | 21 | ||
| 663. | | 663.2 | ||
| [[16/11]], [[19/13]], [[22/15]], [[28/19]] | | [[16/11]], [[19/13]], [[22/15]], [[28/19]] | ||
| Down 5th | | Down 5th | ||
Line 176: | Line 180: | ||
|- | |- | ||
| 22 | | 22 | ||
| 694. | | 694.7 | ||
| [[3/2]] | | [[3/2]] | ||
| Perfect 5th | | Perfect 5th | ||
Line 183: | Line 187: | ||
|- | |- | ||
| 23 | | 23 | ||
| 726. | | 726.3 | ||
| [[26/17]] | | [[26/17]] | ||
| Up 5th | | Up 5th | ||
Line 190: | Line 194: | ||
|- | |- | ||
| 24 | | 24 | ||
| 757. | | 757.9 | ||
| [[20/13]], [[17/11]], [[14/9]] | | [[20/13]], [[17/11]], [[14/9]] | ||
| Aug 5th, dim 6th | | Aug 5th, dim 6th | ||
Line 197: | Line 201: | ||
|- | |- | ||
| 25 | | 25 | ||
| 789. | | 789.5 | ||
| [[11/7]], [[30/19]], [[19/12]] | | [[11/7]], [[30/19]], [[19/12]] | ||
| Upaug 5th, downminor 6th | | Upaug 5th, downminor 6th | ||
Line 204: | Line 208: | ||
|- | |- | ||
| 26 | | 26 | ||
| 821. | | 821.1 | ||
| [[8/5]], [[13/8]] | | [[8/5]], [[13/8]] | ||
| Minor 6th | | Minor 6th | ||
Line 211: | Line 215: | ||
|- | |- | ||
| 27 | | 27 | ||
| 852. | | 852.6 | ||
| [[18/11]], [[28/17]] | | [[18/11]], [[28/17]] | ||
| Mid 6th | | Mid 6th | ||
Line 218: | Line 222: | ||
|- | |- | ||
| 28 | | 28 | ||
| 884. | | 884.2 | ||
| [[5/3]] | | [[5/3]] | ||
| Major 6th | | Major 6th | ||
Line 225: | Line 229: | ||
|- | |- | ||
| 29 | | 29 | ||
| 915. | | 915.8 | ||
| [[32/19]], [[22/13]], [[17/10]] | | [[32/19]], [[22/13]], [[17/10]] | ||
| Upmajor 6th | | Upmajor 6th | ||
Line 232: | Line 236: | ||
|- | |- | ||
| 30 | | 30 | ||
| 947. | | 947.4 | ||
| [[12/7]], [[19/11]], [[26/15]], [[7/4]] | | [[12/7]], [[19/11]], [[26/15]], [[7/4]] | ||
| Aug 6th, dim 7th | | Aug 6th, dim 7th | ||
Line 239: | Line 243: | ||
|- | |- | ||
| 31 | | 31 | ||
| 978. | | 978.9 | ||
| [[30/17]] | | [[30/17]] | ||
| Downminor 7th | | Downminor 7th | ||
Line 246: | Line 250: | ||
|- | |- | ||
| 32 | | 32 | ||
| 1010. | | 1010.5 | ||
| [[16/9]], [[34/19]], [[9/5]] | | [[16/9]], [[34/19]], [[9/5]] | ||
| Minor 7th | | Minor 7th | ||
Line 253: | Line 257: | ||
|- | |- | ||
| 33 | | 33 | ||
| 1042. | | 1042.1 | ||
| [[20/11]], [[11/6]] | | [[20/11]], [[11/6]] | ||
| Mid 7th | | Mid 7th | ||
Line 260: | Line 264: | ||
|- | |- | ||
| 34 | | 34 | ||
| 1073. | | 1073.7 | ||
| [[24/13]], [[13/7]], [[28/15]], [[15/8]] | | [[24/13]], [[13/7]], [[28/15]], [[15/8]] | ||
| Major 7th | | Major 7th | ||
Line 267: | Line 271: | ||
|- | |- | ||
| 35 | | 35 | ||
| 1105. | | 1105.3 | ||
| [[32/17]], [[17/9]], [[36/19]], [[19/10]] | | [[32/17]], [[17/9]], [[36/19]], [[19/10]] | ||
| Upmajor 7th, Downdim 8ve | | Upmajor 7th, Downdim 8ve | ||
Line 274: | Line 278: | ||
|- | |- | ||
| 36 | | 36 | ||
| 1136. | | 1136.8 | ||
| | | | ||
| Aug 7th, dim 8ve | | Aug 7th, dim 8ve | ||
Line 281: | Line 285: | ||
|- | |- | ||
| 37 | | 37 | ||
| 1168. | | 1168.4 | ||
| | | | ||
| Down 8ve | | Down 8ve | ||
Line 288: | Line 292: | ||
|- | |- | ||
| 38 | | 38 | ||
| 1200. | | 1200.0 | ||
| | | | ||
| Perfect 8ve | | Perfect 8ve | ||
Line 294: | Line 298: | ||
| D | | D | ||
|} | |} | ||
<nowiki />* Ups and downs may be substituted with semi-sharps and semi-flats, respectively | <nowiki/>* Ups and downs may be substituted with semi-sharps and semi-flats, respectively | ||
== Notation == | |||
=== Ups and downs notation === | |||
Spoken as up, sharp, upsharp, etc. Note that up can be respelled as downsharp. | |||
{{sharpness-sharp2a}} | |||
=== Quarter-tone notation === | |||
Since a sharp raises by two steps, [[24edo#Notation|quarter-tone accidentals]] can also be used: | |||
{{sharpness-sharp2}} | |||
=== Sagittal notation === | |||
This notation uses the same sagittal sequence as EDOs [[17edo#Sagittal notation|17]], [[24edo#Sagittal notation|24]], and [[31edo#Sagittal notation|31]], is a subset of the notation for [[76edo#Sagittal notation|76-EDO]], and is a superset of the notation for [[19edo#Sagittal notation|19-EDO]]. | |||
==== Evo flavor ==== | |||
<imagemap> | |||
File:38-EDO_Evo_Sagittal.svg | |||
desc none | |||
rect 80 0 300 50 [[Sagittal_notation]] | |||
rect 300 0 679 80 [https://sagittal.org#periodic-table Periodic table of EDOs with sagittal notation] | |||
rect 20 80 130 106 [[33/32]] | |||
default [[File:38-EDO_Evo_Sagittal.svg]] | |||
</imagemap> | |||
==== Revo flavor ==== | |||
<imagemap> | |||
File:38-EDO_Revo_Sagittal.svg | |||
desc none | |||
rect 80 0 300 50 [[Sagittal_notation]] | |||
rect 300 0 703 80 [https://sagittal.org#periodic-table Periodic table of EDOs with sagittal notation] | |||
rect 20 80 130 106 [[33/32]] | |||
default [[File:38-EDO_Revo_Sagittal.svg]] | |||
</imagemap> | |||
==== Evo-SZ flavor ==== | |||
<imagemap> | |||
File:38-EDO_Evo-SZ_Sagittal.svg | |||
desc none | |||
rect 80 0 300 50 [[Sagittal_notation]] | |||
rect 300 0 631 80 [https://sagittal.org#periodic-table Periodic table of EDOs with sagittal notation] | |||
rect 20 80 130 106 [[33/32]] | |||
default [[File:38-EDO_Evo-SZ_Sagittal.svg]] | |||
</imagemap> | |||
Because it contains no Sagittal symbols, this Evo-SZ Sagittal notation is also a Stein-Zimmerman notation. | |||
== Approximation to JI == | |||
=== Interval mappings === | |||
{{Q-odd-limit intervals}} | |||
== Instruments == | == Instruments == | ||
Line 301: | Line 353: | ||
== Music == | == Music == | ||
* [https://www.youtube.com/watch?v=Cw1Cz1ojoSw Canon at the Semitone on The Mother's Malison Theme for Cor Anglais and Violin] | ; [[Bryan Deister]] | ||
* [https://www.youtube.com/shorts/rewy-32BfRs ''Spirit of the Night - Secret of Mana (microtonal cover in 38edo)''] (2025) | |||
; [[Claudi Meneghin]] | |||
* [https://www.youtube.com/watch?v=Cw1Cz1ojoSw Canon at the Semitone on The Mother's Malison Theme for Cor Anglais and Violin] (2022) | |||
[[Category:38edo| ]] <!-- Main article --> | [[Category:38edo| ]] <!-- Main article --> |