38edo: Difference between revisions
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{{ | {{ED intro}} | ||
==Theory== | == Theory == | ||
Since 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. | ||
In [[ | 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. | ||
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]]] | |||
=== Prime harmonics === | |||
{{Harmonics in equal|38}} | {{Harmonics in equal|38}} | ||
== Intervals == | == Intervals == | ||
{| class="wikitable center-1 right-2" | {| class="wikitable center-1 right-2" | ||
|- | |- | ||
! Step | ! Step | ||
! Cents | ! Cents | ||
!19-limit ratios, | ! 19-odd-limit ratios,<br>in 38df val | ||
! colspan="3" | [[Ups and downs notation]]* | |||
! colspan="3" | [[Ups and | ([[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 | ||
| ^A1, vm2 | | ^A1, vm2 | ||
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 | ||
| m2 | | m2 | ||
Line 57: | Line 61: | ||
|- | |- | ||
| 5 | | 5 | ||
| 157. | | 157.9 | ||
|[[12/11]], [[11/10]] | | [[12/11]], [[11/10]] | ||
| Mid 2nd | | Mid 2nd | ||
| ~2 | | ~2 | ||
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 | ||
| M2 | | M2 | ||
Line 71: | Line 75: | ||
|- | |- | ||
| 7 | | 7 | ||
| 221. | | 221.1 | ||
|[[17/15]] | | [[17/15]] | ||
| Upmajor 2nd | | Upmajor 2nd | ||
| ^M2 | | ^M2 | ||
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 | ||
| A2, d3 | | A2, d3 | ||
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 | ||
| vm3 | | vm3 | ||
Line 92: | Line 96: | ||
|- | |- | ||
| 10 | | 10 | ||
| 315. | | 315.8 | ||
|[[6/5]] | | [[6/5]] | ||
| Minor 3rd | | Minor 3rd | ||
| m3 | | m3 | ||
Line 99: | Line 103: | ||
|- | |- | ||
| 11 | | 11 | ||
| 347. | | 347.4 | ||
|[[17/14]], [[11/9]] | | [[17/14]], [[11/9]] | ||
| Mid 3rd | | Mid 3rd | ||
| ~3 | | ~3 | ||
Line 106: | Line 110: | ||
|- | |- | ||
| 12 | | 12 | ||
| 378. | | 378.9 | ||
|[[16/13]], [[5/4]] | | [[16/13]], [[5/4]] | ||
| Major 3rd | | Major 3rd | ||
| M3 | | M3 | ||
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 | ||
| ^M3, vd4 | | ^M3, vd4 | ||
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 | ||
| A3, d4 | | A3, d4 | ||
Line 127: | Line 131: | ||
|- | |- | ||
| 15 | | 15 | ||
| 473. | | 473.7 | ||
|[[17/13]] | | [[17/13]] | ||
| Down 4th | | Down 4th | ||
| v4 | | v4 | ||
Line 134: | Line 138: | ||
|- | |- | ||
| 16 | | 16 | ||
| 505. | | 505.3 | ||
|[[4/3]] | | [[4/3]] | ||
| Perfect 4th | | Perfect 4th | ||
| P4 | | P4 | ||
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 | ||
| ^4 | | ^4 | ||
Line 148: | Line 152: | ||
|- | |- | ||
| 18 | | 18 | ||
| 568. | | 568.4 | ||
|[[18/13]], [[7/5]] | | [[18/13]], [[7/5]] | ||
| Aug 4th | | Aug 4th | ||
| A4 | | A4 | ||
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 | ||
| ^A4, vd5 | | ^A4, vd5 | ||
Line 162: | Line 166: | ||
|- | |- | ||
| 20 | | 20 | ||
| 631. | | 631.6 | ||
|[[10/7]], [[13/9]] | | [[10/7]], [[13/9]] | ||
| Dim 5th | | Dim 5th | ||
| d5 | | d5 | ||
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 | ||
| v5 | | v5 | ||
Line 176: | Line 180: | ||
|- | |- | ||
| 22 | | 22 | ||
| 694. | | 694.7 | ||
|[[3/2]] | | [[3/2]] | ||
| Perfect 5th | | Perfect 5th | ||
| P5 | | P5 | ||
Line 183: | Line 187: | ||
|- | |- | ||
| 23 | | 23 | ||
| 726. | | 726.3 | ||
|[[26/17]] | | [[26/17]] | ||
| Up 5th | | Up 5th | ||
| ^5 | | ^5 | ||
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 | ||
| A5, d6 | | A5, d6 | ||
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 | ||
| ^A5, vm6 | | ^A5, vm6 | ||
Line 204: | Line 208: | ||
|- | |- | ||
| 26 | | 26 | ||
| 821. | | 821.1 | ||
|[[8/5]], [[13/8]] | | [[8/5]], [[13/8]] | ||
| Minor 6th | | Minor 6th | ||
| m6 | | m6 | ||
Line 211: | Line 215: | ||
|- | |- | ||
| 27 | | 27 | ||
| 852. | | 852.6 | ||
|[[18/11]], [[28/17]] | | [[18/11]], [[28/17]] | ||
| Mid 6th | | Mid 6th | ||
| ~6 | | ~6 | ||
Line 218: | Line 222: | ||
|- | |- | ||
| 28 | | 28 | ||
| 884. | | 884.2 | ||
|[[5/3]] | | [[5/3]] | ||
| Major 6th | | Major 6th | ||
| M6 | | M6 | ||
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 | ||
| ^M6 | | ^M6 | ||
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 | ||
| A6, d7 | | A6, d7 | ||
Line 239: | Line 243: | ||
|- | |- | ||
| 31 | | 31 | ||
| 978. | | 978.9 | ||
|[[30/17]] | | [[30/17]] | ||
| Downminor 7th | | Downminor 7th | ||
| vm7 | | vm7 | ||
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 | ||
| m7 | | m7 | ||
Line 253: | Line 257: | ||
|- | |- | ||
| 33 | | 33 | ||
| 1042. | | 1042.1 | ||
|[[20/11]], [[11/6]] | | [[20/11]], [[11/6]] | ||
| Mid 7th | | Mid 7th | ||
| ~7 | | ~7 | ||
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 | ||
| M7 | | M7 | ||
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 | ||
| ^M7, vd8 | | ^M7, vd8 | ||
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>* | <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 == | ||
*[[Lumatone mapping for 38edo]] | * [[Lumatone mapping for 38edo]] | ||
*[[Skip fretting system 38 2 11]] | * [[Skip fretting system 38 2 11]] | ||
== 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| ]] <!-- | [[Category:38edo| ]] <!-- Main article --> | ||
[[Category:Equal divisions of the octave|##]] <!-- 2-digit number --> | [[Category:Equal divisions of the octave|##]] <!-- 2-digit number --> | ||
[[Category:Listen]] | [[Category:Listen]] | ||
[[Category:Todo:add rank 2 temperaments table]] | [[Category:Todo:add rank 2 temperaments table]] |
Latest revision as of 00:05, 16 August 2025
← 37edo | 38edo | 39edo → |
38 equal divisions of the octave (abbreviated 38edo or 38ed2), also called 38-tone equal temperament (38tet) or 38 equal temperament (38et) when viewed under a regular temperament perspective, is the tuning system that divides the octave into 38 equal parts of about 31.6 ¢ each. Each step represents a frequency ratio of 21/38, or the 38th root of 2.
Theory
Since 38 = 2 × 19, it can be thought of as two parallel 19edos. While the halving of the step size lowers consistency and leaves it only mediocre in terms of overall 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 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.
Using the 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 consistent within the 38df val ⟨38 60 88 106 131 140 155 161].
The harmonic series from 1 to 20 is approximated within 38df by the sequence: 38 22 16 12 10 8 8 6 6 5 5 4 4 4 4 3 3 3 3
[Harmonic series 2-20 in 38df]
Prime harmonics
Harmonic | 2 | 3 | 5 | 7 | 11 | 13 | 17 | 19 | 23 | 29 | 31 | |
---|---|---|---|---|---|---|---|---|---|---|---|---|
Error | Absolute (¢) | +0.0 | -7.2 | -7.4 | +10.1 | -14.5 | +12.1 | -10.2 | -13.3 | +3.3 | +12.5 | -8.2 |
Relative (%) | +0.0 | -22.9 | -23.3 | +32.1 | -45.8 | +38.3 | -32.4 | -42.1 | +10.5 | +39.7 | -25.9 | |
Steps (reduced) |
38 (0) |
60 (22) |
88 (12) |
107 (31) |
131 (17) |
141 (27) |
155 (3) |
161 (9) |
172 (20) |
185 (33) |
188 (36) |
Intervals
Step | Cents | 19-odd-limit ratios, in 38df val |
Ups and downs notation*
(EUs: vvA1 and vvd2) | ||
---|---|---|---|---|---|
0 | 0.0 | Perfect 1sn | P1 | D | |
1 | 31.6 | Up 1sn | ^1 | ^D | |
2 | 63.2 | Aug 1sn, dim 2nd | A1, d2 | D# | |
3 | 94.7 | 20/19, 19/18, 18/17, 17/16 | Upaug 1sn, downminor 2nd | ^A1, vm2 | ^D#, vEb |
4 | 126.3 | 16/15, 15/14, 14/13, 13/12 | Minor 2nd | m2 | Eb |
5 | 157.9 | 12/11, 11/10 | Mid 2nd | ~2 | vE |
6 | 189.5 | 10/9, 19/17, 9/8 | Major 2nd | M2 | E |
7 | 221.1 | 17/15 | Upmajor 2nd | ^M2 | ^E |
8 | 252.6 | 8/7, 15/13, 22/19, 7/6 | Aug 2nd, Dim 3rd | A2, d3 | E#, Fb |
9 | 284.2 | 20/17, 13/11, 19/16 | Downminor 3rd | vm3 | vF |
10 | 315.8 | 6/5 | Minor 3rd | m3 | F |
11 | 347.4 | 17/14, 11/9 | Mid 3rd | ~3 | ^F |
12 | 378.9 | 16/13, 5/4 | Major 3rd | M3 | F# |
13 | 410.5 | 24/19, 19/15, 14/11 | Upmajor 3rd, Downdim 4th | ^M3, vd4 | ^F#, vGb |
14 | 442.1 | 9/7, 22/17, 13/10 | Aug 3rd, dim 4th | A3, d4 | Gb |
15 | 473.7 | 17/13 | Down 4th | v4 | vG |
16 | 505.3 | 4/3 | Perfect 4th | P4 | G |
17 | 536.8 | 19/14, 15/11, 26/19, 11/8 | Up 4th | ^4 | ^G |
18 | 568.4 | 18/13, 7/5 | Aug 4th | A4 | G# |
19 | 600.0 | 24/17, 17/12 | Upaug 4th, downdim 5th | ^A4, vd5 | ^G#, vAb |
20 | 631.6 | 10/7, 13/9 | Dim 5th | d5 | Ab |
21 | 663.2 | 16/11, 19/13, 22/15, 28/19 | Down 5th | v5 | vA |
22 | 694.7 | 3/2 | Perfect 5th | P5 | A |
23 | 726.3 | 26/17 | Up 5th | ^5 | ^A |
24 | 757.9 | 20/13, 17/11, 14/9 | Aug 5th, dim 6th | A5, d6 | A# |
25 | 789.5 | 11/7, 30/19, 19/12 | Upaug 5th, downminor 6th | ^A5, vm6 | ^A#, vBb |
26 | 821.1 | 8/5, 13/8 | Minor 6th | m6 | Bb |
27 | 852.6 | 18/11, 28/17 | Mid 6th | ~6 | vB |
28 | 884.2 | 5/3 | Major 6th | M6 | B |
29 | 915.8 | 32/19, 22/13, 17/10 | Upmajor 6th | ^M6 | ^B |
30 | 947.4 | 12/7, 19/11, 26/15, 7/4 | Aug 6th, dim 7th | A6, d7 | B#, Cb |
31 | 978.9 | 30/17 | Downminor 7th | vm7 | vC |
32 | 1010.5 | 16/9, 34/19, 9/5 | Minor 7th | m7 | C |
33 | 1042.1 | 20/11, 11/6 | Mid 7th | ~7 | ^C |
34 | 1073.7 | 24/13, 13/7, 28/15, 15/8 | Major 7th | M7 | C# |
35 | 1105.3 | 32/17, 17/9, 36/19, 19/10 | Upmajor 7th, Downdim 8ve | ^M7, vd8 | ^C#, vDb |
36 | 1136.8 | Aug 7th, dim 8ve | A7, d8 | Db | |
37 | 1168.4 | Down 8ve | v8 | vD | |
38 | 1200.0 | Perfect 8ve | P8 | D |
* 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.
Step offset | −4 | −3 | −2 | −1 | 0 | +1 | +2 | +3 | +4 |
---|---|---|---|---|---|---|---|---|---|
Symbol | ![]() |
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Quarter-tone notation
Since a sharp raises by two steps, quarter-tone accidentals can also be used:
Step offset | −4 | −3 | −2 | −1 | 0 | +1 | +2 | +3 | +4 |
---|---|---|---|---|---|---|---|---|---|
Symbol | ![]() |
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Sagittal notation
This notation uses the same sagittal sequence as EDOs 17, 24, and 31, is a subset of the notation for 76-EDO, and is a superset of the notation for 19-EDO.
Evo flavor

Revo flavor

Evo-SZ flavor

Because it contains no Sagittal symbols, this Evo-SZ Sagittal notation is also a Stein-Zimmerman notation.
Approximation to JI
Interval mappings
The following tables show how 15-odd-limit intervals are represented in 38edo. Prime harmonics are in bold; inconsistent intervals are in italics.
Interval and complement | Error (abs, ¢) | Error (rel, %) |
---|---|---|
1/1, 2/1 | 0.000 | 0.0 |
11/9, 18/11 | 0.040 | 0.1 |
15/11, 22/15 | 0.109 | 0.3 |
5/3, 6/5 | 0.148 | 0.5 |
13/7, 14/13 | 1.982 | 6.3 |
15/13, 26/15 | 4.891 | 15.5 |
13/11, 22/13 | 4.999 | 15.8 |
13/9, 18/13 | 5.039 | 16.0 |
15/14, 28/15 | 6.873 | 21.8 |
11/7, 14/11 | 6.982 | 22.1 |
9/7, 14/9 | 7.021 | 22.2 |
9/5, 10/9 | 7.070 | 22.4 |
11/10, 20/11 | 7.109 | 22.5 |
3/2, 4/3 | 7.218 | 22.9 |
11/6, 12/11 | 7.258 | 23.0 |
5/4, 8/5 | 7.366 | 23.3 |
7/4, 8/7 | 10.121 | 32.1 |
13/8, 16/13 | 12.104 | 38.3 |
13/10, 20/13 | 12.109 | 38.3 |
13/12, 24/13 | 12.257 | 38.8 |
7/5, 10/7 | 14.091 | 44.6 |
7/6, 12/7 | 14.239 | 45.1 |
9/8, 16/9 | 14.436 | 45.7 |
11/8, 16/11 | 14.476 | 45.8 |
15/8, 16/15 | 14.585 | 46.2 |
Interval and complement | Error (abs, ¢) | Error (rel, %) |
---|---|---|
1/1, 2/1 | 0.000 | 0.0 |
11/9, 18/11 | 0.040 | 0.1 |
15/11, 22/15 | 0.109 | 0.3 |
5/3, 6/5 | 0.148 | 0.5 |
13/7, 14/13 | 1.982 | 6.3 |
9/5, 10/9 | 7.070 | 22.4 |
11/10, 20/11 | 7.109 | 22.5 |
3/2, 4/3 | 7.218 | 22.9 |
11/6, 12/11 | 7.258 | 23.0 |
5/4, 8/5 | 7.366 | 23.3 |
7/4, 8/7 | 10.121 | 32.1 |
13/8, 16/13 | 12.104 | 38.3 |
9/8, 16/9 | 14.436 | 45.7 |
11/8, 16/11 | 14.476 | 45.8 |
15/8, 16/15 | 14.585 | 46.2 |
7/6, 12/7 | 17.340 | 54.9 |
7/5, 10/7 | 17.488 | 55.4 |
13/12, 24/13 | 19.322 | 61.2 |
13/10, 20/13 | 19.470 | 61.7 |
9/7, 14/9 | 24.558 | 77.8 |
11/7, 14/11 | 24.597 | 77.9 |
15/14, 28/15 | 24.706 | 78.2 |
13/9, 18/13 | 26.540 | 84.0 |
13/11, 22/13 | 26.580 | 84.2 |
15/13, 26/15 | 26.688 | 84.5 |