87edt

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← 86edt87edt88edt →
Prime factorization 3 × 29
Step size 21.8616¢ 
Octave 55\87edt (1202.39¢)
Consistency limit 4
Distinct consistency limit 4

Division of the third harmonic into 87 equal parts (87EDT) is related to 55 edo, but with the 3/1 rather than the 2/1 being just. The octave is about 2.3853 cents stretched and the step size is about 21.8616 cents. Unlike 55edo, it is only consistent up to the 4-integer-limit, with discrepancy for the 5th harmonic.

Lookalikes: 55edo, 142ed6, 154ed7

Intervals

Steps Cents Approximate Ratios
0 0 1/1
1 21.862
2 43.723 38/37, 39/38, 40/39, 41/40
3 65.585 27/26, 28/27
4 87.446 20/19, 41/39
5 109.308 33/31
6 131.169 14/13, 41/38
7 153.031 12/11
8 174.892 21/19, 31/28, 41/37
9 196.754 37/33
10 218.616 17/15
11 240.477 23/20, 31/27
12 262.339
13 284.2 20/17, 33/28
14 306.062 31/26, 37/31
15 327.923 23/19, 29/24
16 349.785 11/9, 38/31
17 371.646 26/21, 36/29
18 393.508
19 415.369 14/11, 33/26
20 437.231 9/7
21 459.093 30/23
22 480.954 29/22, 37/28
23 502.816
24 524.677 23/17
25 546.539 37/27
26 568.4
27 590.262 38/27
28 612.123 37/26
29 633.985 13/9
30 655.847 19/13
31 677.708 34/23, 40/27
32 699.57 3/2
33 721.431 41/27
34 743.293 20/13
35 765.154 14/9
36 787.016 41/26
37 808.877
38 830.739 21/13
39 852.601 18/11
40 874.462
41 896.324
42 918.185 17/10
43 940.047 31/18
44 961.908
45 983.77 30/17
46 1005.631 34/19
47 1027.493 29/16, 38/21
48 1049.354 11/6
49 1071.216 13/7
50 1093.078
51 1114.939 40/21
52 1136.801 27/14
53 1158.662 39/20, 41/21
54 1180.524
55 1202.385 2/1
56 1224.247
57 1246.108 37/18, 39/19
58 1267.97 27/13
59 1289.832 40/19
60 1311.693
61 1333.555 41/19
62 1355.416
63 1377.278 31/14
64 1399.139
65 1421.001
66 1442.862 23/10
67 1464.724 7/3
68 1486.586 26/11, 33/14
69 1508.447
70 1530.309 29/12
71 1552.17 27/11
72 1574.032
73 1595.893
74 1617.755 28/11
75 1639.616
76 1661.478
77 1683.339 37/14
78 1705.201
79 1727.063 19/7
80 1748.924 11/4
81 1770.786 39/14
82 1792.647 31/11
83 1814.509
84 1836.37 26/9
85 1858.232 38/13, 41/14
86 1880.093
87 1901.955 3/1

Harmonics

Approximation of harmonics in 87edt
Harmonic 2 3 4 5 6 7 8 9 10 11 12
Error Absolute (¢) +2.39 +0.00 +4.77 -9.90 +2.39 -2.15 +7.16 +0.00 -7.51 +2.38 +4.77
Relative (%) +10.9 +0.0 +21.8 -45.3 +10.9 -9.8 +32.7 +0.0 -34.4 +10.9 +21.8
Steps
(reduced)
55
(55)
87
(0)
110
(23)
127
(40)
142
(55)
154
(67)
165
(78)
174
(0)
182
(8)
190
(16)
197
(23)
Approximation of harmonics in 87edt
Harmonic 13 14 15 16 17 18 19 20 21 22 23
Error Absolute (¢) -2.63 +0.24 -9.90 +9.54 -7.97 +2.39 -3.77 -5.13 -2.15 +4.76 -6.61
Relative (%) -12.0 +1.1 -45.3 +43.6 -36.4 +10.9 -17.3 -23.4 -9.8 +21.8 -30.2
Steps
(reduced)
203
(29)
209
(35)
214
(40)
220
(46)
224
(50)
229
(55)
233
(59)
237
(63)
241
(67)
245
(71)
248
(74)