87edt

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← 86edt 87edt 88edt →
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 21.9
2 43.7 38/37, 39/38, 40/39, 41/40
3 65.6 27/26, 28/27
4 87.4 20/19, 41/39
5 109.3 33/31
6 131.2 14/13, 41/38
7 153 12/11
8 174.9 21/19, 31/28, 41/37
9 196.8 37/33
10 218.6 17/15
11 240.5 23/20, 31/27
12 262.3
13 284.2 20/17, 33/28
14 306.1 31/26, 37/31
15 327.9 23/19, 29/24
16 349.8 11/9, 38/31
17 371.6 26/21, 36/29
18 393.5
19 415.4 14/11, 33/26
20 437.2 9/7
21 459.1 30/23
22 481 29/22, 37/28
23 502.8
24 524.7 23/17
25 546.5 37/27
26 568.4
27 590.3 38/27
28 612.1 37/26
29 634 13/9
30 655.8 19/13
31 677.7 34/23, 40/27
32 699.6 3/2
33 721.4 41/27
34 743.3 20/13
35 765.2 14/9
36 787 41/26
37 808.9
38 830.7 21/13
39 852.6 18/11
40 874.5
41 896.3
42 918.2 17/10
43 940 31/18
44 961.9
45 983.8 30/17
46 1005.6 34/19
47 1027.5 29/16, 38/21
48 1049.4 11/6
49 1071.2 13/7
50 1093.1
51 1114.9 40/21
52 1136.8 27/14
53 1158.7 39/20, 41/21
54 1180.5
55 1202.4 2/1
56 1224.2
57 1246.1 37/18, 39/19
58 1268 27/13
59 1289.8 40/19
60 1311.7
61 1333.6 41/19
62 1355.4
63 1377.3 31/14
64 1399.1
65 1421
66 1442.9 23/10
67 1464.7 7/3
68 1486.6 26/11, 33/14
69 1508.4
70 1530.3 29/12
71 1552.2 27/11
72 1574
73 1595.9
74 1617.8 28/11
75 1639.6
76 1661.5
77 1683.3 37/14
78 1705.2
79 1727.1 19/7
80 1748.9 11/4
81 1770.8 39/14
82 1792.6 31/11
83 1814.5
84 1836.4 26/9
85 1858.2 38/13, 41/14
86 1880.1
87 1902 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)