30edt: Difference between revisions
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Because 19edo has the 3rd, 5th, 7th, and 13th harmonics all flat (the latter two very flat), it benefits greatly from octave stretching. 30edt is one possible alternative; at the cost of sharpening the octave, it achieves much better matches to the odd harmonics; the 3 is by definition just, the 5 slightly sharp, and the 7 and 13 slightly flat. | Because 19edo has the 3rd, 5th, 7th, and 13th harmonics all flat (the latter two very flat), it benefits greatly from octave stretching. 30edt is one possible alternative; at the cost of sharpening the octave, it achieves much better matches to the odd harmonics; the 3 is by definition just, the 5 slightly sharp, and the 7 and 13 slightly flat. | ||
===<span style="font-size: 1.4em;">Intervals of 30edt</span>=== | ===<span style="font-size: 1.4em;">Intervals of 30edt</span>=== | ||
| Line 52: | Line 50: | ||
| | 443.7895 | | | 443.7895 | ||
| | 9/7 | | | 9/7 | ||
| | E#/ | | | E#/Fbb | ||
|- | |- | ||
| | 8 | | | 8 | ||
| | 507.188 | | | 507.188 | ||
| | [[4/3|4/3]] | | | [[4/3|4/3]] | ||
| | | | | Ex/Fb | ||
|- | |- | ||
| | 9 | | | 9 | ||
| | 570.5865 | | | 570.5865 | ||
| | 7/5 | | | 7/5 | ||
| | F | | | F | ||
|- | |- | ||
| | 10 | | | 10 | ||
| | 633.985 | | | 633.985 | ||
| | [[13/9|13/9]] | | | [[13/9|13/9]] | ||
| | | | | F#/Gb | ||
|- | |- | ||
| | 11 | | | 11 | ||
| Line 107: | Line 105: | ||
| | 1141.173 | | | 1141.173 | ||
| | <span style="color: #660000;">[[27/14|27/14]]</span> | | | <span style="color: #660000;">[[27/14|27/14]]</span> | ||
| | J#/ | | | J#/Kbb | ||
|- | |- | ||
| | 19 | | | 19 | ||
| | 1204.5715 | | | 1204.5715 | ||
| | 2/1 | | | 2/1 | ||
| | | | | Jx/Kb | ||
|- | |- | ||
| | 20 | | | 20 | ||
| | 1267.970 | | | 1267.970 | ||
| | [[27/13|27/13]] | | | [[27/13|27/13]] | ||
| | K | | | K | ||
|- | |- | ||
| | 21 | | | 21 | ||
| | 1331.3685 | | | 1331.3685 | ||
| | 28/13 | | | 28/13 | ||
| | | | | K#/Lb | ||
|- | |- | ||
| | 22 | | | 22 | ||
| Line 147: | Line 145: | ||
| | 1648.361 | | | 1648.361 | ||
| | [[13/5|13/5]] ([[13/10|13/10]] plus an octave) | | | [[13/5|13/5]] ([[13/10|13/10]] plus an octave) | ||
| | A#/ | | | A#/Bbb | ||
|- | |- | ||
| | 27 | | | 27 | ||
| | 1711.7595 | | | 1711.7595 | ||
| | 8/3 | | | 8/3 | ||
| | | | | Ax/Bb | ||
|- | |- | ||
| | 28 | | | 28 | ||
| | 1775.158 | | | 1775.158 | ||
| | [[14/5|14/5]] ([[7/5|7/5]] plus an octave) | | | [[14/5|14/5]] ([[7/5|7/5]] plus an octave) | ||
| | B | | | B | ||
|- | |- | ||
| | 29 | | | 29 | ||
| | 1838.5565 | | | 1838.5565 | ||
| | 26/9 | | | 26/9 | ||
| | | | | B#/Cb | ||
|- | |- | ||
| | 30 | | | 30 | ||
| Line 174: | Line 172: | ||
30edt also contains all the MOS contained in 15edt, being the double of this equal division. Being even, 30edt introduces | 30edt also contains all the MOS contained in 15edt, being the double of this equal division. Being even, 30edt introduces | ||
MOS with an even number of periods per tritave such as a 6L 6s similar to Hexe Dodecatonic. This MOS has a period of 1/6 of the tritave and the generator is a single or double step. The major scale is sLsLsLsLsLsL, and the minor scale is LsLsLsLsLsLs. Being a "real" 3/2, the interval of 11 degrees generates an unfair Sigma scale of 8L 3s and the major scale is | MOS with an even number of periods per tritave such as a 6L 6s similar to Hexe Dodecatonic. This MOS has a period of 1/6 of the tritave and the generator is a single or double step. The major scale is sLsLsLsLsLsL, and the minor scale is LsLsLsLsLsLs. Being a "real" 3/2, the interval of 11 degrees generates an unfair Sigma scale of 8L 3s and the major scale is LLLsLLLsLLs. The sharp 9/7 of 7 degrees, in addition to generating a Lambda MOS will generate a 4L 9s unfair Superlambda MOS which does not border on being atonal as the 17edt rendition does. | ||
----- | ----- | ||
| Line 180: | Line 178: | ||
==='''Compositions in 30edt'''=== | ==='''Compositions in 30edt'''=== | ||
<ul><li>"[https://soundcloud.com/mason-l-green/room-full-of-steam Room Full Of Steam]", Mason Green. In the key of "Eb subminor".</li></ul> [[Category:edt]] | <ul><li>"[https://soundcloud.com/mason-l-green/room-full-of-steam Room Full Of Steam]", Mason Green. In the key of "Eb subminor".</li></ul> | ||
[[Category:edt]] | |||
[[Category:listen]] | [[Category:listen]] | ||
Revision as of 18:34, 2 December 2018
30edt (30 equal division of the tritave) is a stretched version of 19edo, but with the 3:1 rather than the 2:1 being just. The octave is about 4.5 cents sharp and the step size about 63.4 cents.
Because 19edo has the 3rd, 5th, 7th, and 13th harmonics all flat (the latter two very flat), it benefits greatly from octave stretching. 30edt is one possible alternative; at the cost of sharpening the octave, it achieves much better matches to the odd harmonics; the 3 is by definition just, the 5 slightly sharp, and the 7 and 13 slightly flat.
Intervals of 30edt
| Degrees | Cents | Approximate Ratios | Sigma scale name |
| 0 | 0 | 1/1 | C |
| 1 | 63.3985 | 28/27, 27/26 | C#/Dbb |
| 2 | 126.797 | 14/13, 15/14, 16/15, 29/27 | Cx/Db |
| 3 | 190.1955 | 10/9~9/8 | D |
| 4 | 253.594 | 15/13 | D#/Ebb |
| 5 | 316.9925 | 6/5 | Dx/Eb |
| 6 | 380.391 | 5/4 | E |
| 7 | 443.7895 | 9/7 | E#/Fbb |
| 8 | 507.188 | 4/3 | Ex/Fb |
| 9 | 570.5865 | 7/5 | F |
| 10 | 633.985 | 13/9 | F#/Gb |
| 11 | 697.3835 | 3/2 | G |
| 12 | 760.782 | 14/9 | G#/Hbb |
| 13 | 824.1805 | 8/5 | Gx/Hb |
| 14 | 887.579 | 5/3 | H |
| 15 | 950.9775 | 19/11 | H#/Jbb |
| 16 | 1014.376 | 9/5 | Hx/Jb |
| 17 | 1077.7745 | 13/7 | J |
| 18 | 1141.173 | 27/14 | J#/Kbb |
| 19 | 1204.5715 | 2/1 | Jx/Kb |
| 20 | 1267.970 | 27/13 | K |
| 21 | 1331.3685 | 28/13 | K#/Lb |
| 22 | 1394.767 | 9/4 (9/8 plus an octave) | L |
| 23 | 1458.1655 | 7/3 | L#/Abb |
| 24 | 1521.564 | 12/5 (6/5 plus an octave) | Lx/Ab |
| 25 | 1584.9625 | 5/2 | A |
| 26 | 1648.361 | 13/5 (13/10 plus an octave) | A#/Bbb |
| 27 | 1711.7595 | 8/3 | Ax/Bb |
| 28 | 1775.158 | 14/5 (7/5 plus an octave) | B |
| 29 | 1838.5565 | 26/9 | B#/Cb |
| 30 | 1901.955 | 3/1 | C |
30edt contains all 19edo intervals within 3/1, all temepered progressively sharper. The accumulation of the .241 cent sharpening of the unit step relative to 19edo leads to the excellent 6edt approximations of 6/5 and 5/2. Non-redundantly with simpler edts, the 41 degree ~9/2 is only .6615 cents flatter than that in 6edo.
30edt also contains all the MOS contained in 15edt, being the double of this equal division. Being even, 30edt introduces
MOS with an even number of periods per tritave such as a 6L 6s similar to Hexe Dodecatonic. This MOS has a period of 1/6 of the tritave and the generator is a single or double step. The major scale is sLsLsLsLsLsL, and the minor scale is LsLsLsLsLsLs. Being a "real" 3/2, the interval of 11 degrees generates an unfair Sigma scale of 8L 3s and the major scale is LLLsLLLsLLs. The sharp 9/7 of 7 degrees, in addition to generating a Lambda MOS will generate a 4L 9s unfair Superlambda MOS which does not border on being atonal as the 17edt rendition does.
Compositions in 30edt
- "Room Full Of Steam", Mason Green. In the key of "Eb subminor".