26edt

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The 26 equal division of 3 (the tritave), divides it into 26 equal parts of 73.152 cents each, corresponding to 16.404 edo. It is contorted in the 7-limit, tempering out the same commas, 245/243 and 3125/3087, as 13edt. In the 11-limit it tempers out 125/121 and 3087/3025, in the 13-limit 175/169, 147/143, and 847/845, and in the 17-limit 119/117. It is the seventh zeta peak tritave division. A reason to double 13edt to 26edt is to approximate the 8th, 13th, 17th, 20th, and 22nd harmonics particularly well. Moreover, it has an exaggerated diatonic scale with 11:16:21 supermajor triads, though only the 16:11 is particularly just due to its best 16 still being 28.04 cents sharp, or just about as bad as the 25 of 12edo (which is 27.373 cents sharp, an essentially just 100:63).

Intervals[edit]

Steps Cents BP nonatonic degree Diatonic degree Corresponding JI intervals Comments Generator for...
1 73.15 Sa1/sd2 A1/dd2 25/24
2 146.3 A1/m2 AA1/sm2 27/25~49/45
3 219.5 N2 m2 9/8~312/275
4 292.6 M2/d3 M2 25/21~13/11
5 365.8 Sa2/sd3 SM2/dd3 5/4~243/196 False 11/9
6 438.9 A2/P3/d4 AA2/sm3 9/7
7 512.1 Sa3/sd4 m3 27/20 False 21/16
8 585.2 A3/m4/d5 M3 7/5
9 658.4 N4/sd5 SM3/dd4 16/11 False 13/9
10 731.5 M4/m5 AA3/d4 75/49 False 3/2
11 804.7 Sa4/N5 P4 8/5 False 11/7
12 877.8 A4/M5/d6 A4 5/3 False 27/16
13 951.0 Sa5/sd6 AA4/dd5 125/72
14 1024.1 A5/m6/d7 d5 9/5 False 16/9
15 1097.3 N6/sd7 P5 15/8 False 21/11
16 1170.4 M6/m7 A5/dd6 49/25 False 2/1
17 1243.6 Sa6/N7 AA5/sm6 33/16 False 27/13
18 1316.7 A6/M7/d8 m6 15/7
19 1389.9 Sa7/sd8 M6 20/9 False 16/7
20 1463.0 A7/P8/d9 SM6/dd7 7/3
21 1536.2 Sa8/sd9 AA6/sm7 12/5~196/81 False 27/11
22 1609.3 A8/m9 m7 63/25~33/13
23 1682.5 N9 M7 8/3~275/104
24 1755.65 M9/d10 SM7/dd8 25/9~135/49
25 1828.8 Sa9/sd10 A7/d8 72/25
26 1902.0 A9/P10 P8 3/1 Tritave

It is a weird coincidence how 26edt intones any 26edo intervals within plus or minus 6.5 cents when it is supposed to have nothing to do with this other tuning:

26edt 26edo Discrepancy
365.761 369.231 -3.47
512.065 507.692 +4.373
877.825 876.923 +0.902
1243.586 1246.154 -2.168
1389.89 1384.615 +5.275
1755.651 1753.846 +1.805
2121.411 2123.077 -1.666
2633.476 2630.769 +2.647

…and so on

It's not actually a coincidence. It is simply a demonstration of rational approximations to log₂(3). In this table are shown 8/5, 11/7, 19/12, 27/17, 30/19, 38/24, 46/29, 57/36. So all this table does is demonstrate that {{#rreplace: 5edo, 7edo, 12edo, 17edo, 19edo, 24edo, 29edo, 36edo|/(\d+)(\D+)?/|\1\2}} are good for 3-limit.

The Eel And Loach To Attack In Lasciviousness Are Insane play by Omega9