45zpi
45 zeta peak index (abbreviated 45zpi), is the equal-step tuning system obtained from the 45th peak of the Riemann zeta function.
Tuning | Strength | Closest EDO | Integer limit | ||||||
---|---|---|---|---|---|---|---|---|---|
ZPI | Steps per octave | Step size (cents) | Height | Integral | Gap | EDO | Octave (cents) | Consistent | Distinct |
45zpi | 14.5944346577250 | 82.2231232756126 | 2.097730 | 0.344839 | 10.594800 | 15edo | 1233.34684913419 | 2 | 2 |
Theory
45zpi is characterized by a very broad octave error, yet it maintains a quite decent zeta strength. This combination makes it an ideal candidate for no-octave tuning applications.
No other zeta peak indexes exhibit both a larger octave error and greater zeta height than 45zpi.
45zpi supports a complex chord structure with ratios of 1:3:4:5:7:9:13:15:18:19:20:21:22:23:24:25, which further exemplifies its capabilities.
The closest zeta peak indexes to 45zpi that exceed its strength are 42zpi and 47zpi, though 43zpi is nearly as strong as 45zpi.
Harmonic series
Harmonic | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Error | Absolute (¢) | +33.3 | -10.8 | -15.5 | +9.3 | +22.5 | +2.3 | +17.8 | -21.6 | -39.6 | -40.2 | -26.4 | -0.5 | +35.7 | -1.6 | -31.1 |
Relative (%) | +40.6 | -13.2 | -18.9 | +11.3 | +27.4 | +2.8 | +21.7 | -26.3 | -48.2 | -48.8 | -32.1 | -0.6 | +43.4 | -1.9 | -37.8 | |
Step | 15 | 23 | 29 | 34 | 38 | 41 | 44 | 46 | 48 | 50 | 52 | 54 | 56 | 57 | 58 |
Harmonic | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Error | Absolute (¢) | +28.4 | +11.7 | +0.3 | -6.3 | -8.5 | -6.8 | -1.5 | +7.0 | +18.5 | +32.9 | -32.5 | -13.2 | +8.3 | +31.8 | -25.0 | +2.3 |
Relative (%) | +34.6 | +14.2 | +0.4 | -7.6 | -10.3 | -8.3 | -1.9 | +8.5 | +22.6 | +40.0 | -39.5 | -16.1 | +10.1 | +38.7 | -30.4 | +2.8 | |
Step | 60 | 61 | 62 | 63 | 64 | 65 | 66 | 67 | 68 | 69 | 69 | 70 | 71 | 72 | 72 | 73 |
Intervals
JI ratios are comprised of 32-integer limit ratios, and are stylized as follows to indicate their accuracy:
|
Whole tone = 13 steps Limma = 4 steps Apotome = 9 steps | |||
Degree | Cents | Ratios | Ups and Downs Notation | Step |
---|---|---|---|---|
0 | 0.000 | P1 | 0 | |
1 | 82.223 | 32/31, 31/30, 30/29, 29/28, 28/27, 27/26, 26/25, 25/24, 24/23, 23/22, 22/21, 21/20, 20/19, 19/18, 18/17, 17/16, 16/15, 31/29, 15/14 | ^m2 | 5 |
2 | 164.446 | 29/27, 14/13, 27/25, 13/12, 25/23, 12/11, 23/21, 11/10, 32/29, 21/19, 31/28, 10/9, 29/26, 19/17, 28/25, 9/8 | vvvM2 | 10 |
3 | 246.669 | 26/23, 17/15, 25/22, 8/7, 31/27, 23/20, 15/13, 22/19, 29/25, 7/6, 27/23, 20/17 | ^^M2, vvm3 | 15 |
4 | 328.892 | 13/11, 32/27, 19/16, 25/21, 31/26, 6/5, 29/24, 23/19, 17/14, 28/23, 11/9, 27/22, 16/13, 21/17, 26/21 | ^^^m3 | 20 |
5 | 411.116 | 31/25, 5/4, 29/23, 24/19, 19/15, 14/11, 23/18, 32/25, 9/7, 31/24, 22/17 | vM3 | 25 |
6 | 493.339 | 13/10, 30/23, 17/13, 21/16, 25/19, 29/22, 4/3, 31/23, 27/20, 23/17, 19/14 | P4 | 30 |
7 | 575.562 | 15/11, 26/19, 11/8, 29/21, 18/13, 25/18, 32/23, 7/5, 31/22, 24/17, 17/12, 27/19 | v4A4 | 35 |
8 | 657.785 | 10/7, 23/16, 13/9, 29/20, 16/11, 19/13, 22/15, 25/17, 28/19, 31/21 | vvv5 | 40 |
9 | 740.008 | 3/2, 32/21, 29/19, 26/17, 23/15, 20/13, 17/11, 31/20, 14/9, 25/16 | ^^5, vvm6 | 45 |
10 | 822.231 | 11/7, 30/19, 19/12, 27/17, 8/5, 29/18, 21/13, 13/8, 31/19, 18/11, 23/14 | ^^^m6 | 50 |
11 | 904.454 | 28/17, 5/3, 32/19, 27/16, 22/13, 17/10, 29/17, 12/7, 31/18 | vM6 | 55 |
12 | 986.677 | 19/11, 26/15, 7/4, 30/17, 23/13, 16/9, 25/14, 9/5 | m7 | 60 |
13 | 1068.901 | 29/16, 20/11, 31/17, 11/6, 24/13, 13/7, 28/15, 15/8, 32/17, 17/9 | v4M7 | 65 |
14 | 1151.124 | 19/10, 21/11, 23/12, 25/13, 27/14, 29/15, 31/16 | ^M7 | 70 |
15 | 1233.347 | 2/1, 31/15, 29/14, 27/13, 25/12 | ^^1 +1 oct, vvm2 +1 oct | 75 |
16 | 1315.570 | 23/11, 21/10, 19/9, 17/8, 32/15, 15/7, 28/13, 13/6, 24/11 | ^^^m2 +1 oct | 80 |
17 | 1397.793 | 11/5, 31/14, 20/9, 29/13, 9/4, 25/11, 16/7 | vM2 +1 oct | 85 |
18 | 1480.016 | 23/10, 30/13, 7/3, 26/11, 19/8, 31/13, 12/5 | m3 +1 oct | 90 |
19 | 1562.239 | 29/12, 17/7, 22/9, 27/11, 32/13, 5/2 | v4M3 +1 oct | 95 |
20 | 1644.462 | 28/11, 23/9, 18/7, 31/12, 13/5, 21/8, 29/11 | ^M3 +1 oct | 100 |
21 | 1726.686 | 8/3, 27/10, 19/7, 30/11, 11/4 | ^^4 +1 oct | 105 |
22 | 1808.909 | 25/9, 14/5, 31/11, 17/6, 20/7, 23/8, 26/9, 29/10, 32/11 | ^^^d5 +1 oct | 110 |
23 | 1891.132 | 3/1 | v5 +1 oct | 115 |
24 | 1973.355 | 31/10, 28/9, 25/8, 22/7, 19/6, 16/5 | m6 +1 oct | 120 |
25 | 2055.578 | 29/9, 13/4, 23/7, 10/3 | v4M6 +1 oct | 125 |
26 | 2137.801 | 27/8, 17/5, 24/7, 31/9, 7/2 | ^M6 +1 oct | 130 |
27 | 2220.024 | 32/9, 25/7, 18/5, 29/8, 11/3 | ^^m7 +1 oct | 135 |
28 | 2302.247 | 26/7, 15/4, 19/5, 23/6, 27/7 | vvM7 +1 oct | 140 |
29 | 2384.471 | 31/8, 4/1 | v1 +2 oct | 145 |
30 | 2466.694 | 29/7, 25/6, 21/5, 17/4 | m2 +2 oct | 150 |
31 | 2548.917 | 30/7, 13/3, 22/5, 31/7 | v4M2 +2 oct | 155 |
32 | 2631.140 | 9/2, 32/7, 23/5, 14/3 | ^M2 +2 oct | 160 |
33 | 2713.363 | 19/4, 24/5, 29/6 | ^^m3 +2 oct | 165 |
34 | 2795.586 | 5/1 | vvM3 +2 oct | 170 |
35 | 2877.809 | 31/6, 26/5, 21/4, 16/3 | v4 +2 oct | 175 |
36 | 2960.032 | 27/5, 11/2, 28/5 | ^44 +2 oct | 180 |
37 | 3042.256 | 17/3, 23/4, 29/5 | v45 +2 oct | 185 |
38 | 3124.479 | 6/1, 31/5 | ^5 +2 oct | 190 |
39 | 3206.702 | 25/4, 19/3, 32/5, 13/2 | ^^m6 +2 oct | 195 |
40 | 3288.925 | 20/3, 27/4 | vvM6 +2 oct | 200 |
41 | 3371.148 | 7/1 | vm7 +2 oct | 205 |
42 | 3453.371 | 29/4, 22/3, 15/2 | ^4m7 +2 oct | 210 |
43 | 3535.594 | 23/3, 31/4 | M7 +2 oct | 215 |
44 | 3617.817 | 8/1 | ^1 +3 oct | 220 |
45 | 3700.041 | 25/3, 17/2, 26/3 | ^^m2 +3 oct | 225 |
46 | 3782.264 | 9/1 | vvM2 +3 oct | 230 |
47 | 3864.487 | 28/3, 19/2 | vm3 +3 oct | 235 |
48 | 3946.710 | 29/3, 10/1 | ^4m3 +3 oct | 240 |
49 | 4028.933 | 31/3 | M3 +3 oct | 245 |
50 | 4111.156 | 21/2, 32/3, 11/1 | ^4 +3 oct | 250 |
51 | 4193.379 | 23/2 | vvvA4 +3 oct | 255 |
52 | 4275.602 | 12/1 | vv5 +3 oct | 260 |
53 | 4357.826 | 25/2 | vm6 +3 oct | 265 |
54 | 4440.049 | 13/1 | ^4m6 +3 oct | 270 |
55 | 4522.272 | 27/2 | M6 +3 oct | 275 |
56 | 4604.495 | 14/1, 29/2 | ^m7 +3 oct | 280 |
57 | 4686.718 | 15/1 | vvvM7 +3 oct | 285 |
58 | 4768.941 | 31/2, 16/1 | ^^M7 +3 oct, vv1 +4 oct | 290 |
59 | 4851.164 | vm2 +4 oct | 295 | |
60 | 4933.387 | 17/1 | ^4m2 +4 oct | 300 |
61 | 5015.611 | 18/1 | M2 +4 oct | 305 |
62 | 5097.834 | 19/1 | ^m3 +4 oct | 310 |
63 | 5180.057 | 20/1 | vvvM3 +4 oct | 315 |
64 | 5262.280 | 21/1 | ^^M3 +4 oct, vv4 +4 oct | 320 |
65 | 5344.503 | 22/1 | ^^^4 +4 oct | 325 |
66 | 5426.726 | 23/1 | ^4d5 +4 oct | 330 |
67 | 5508.949 | 24/1 | P5 +4 oct | 335 |
68 | 5591.172 | 25/1 | ^m6 +4 oct | 340 |
69 | 5673.396 | 26/1, 27/1 | vvvM6 +4 oct | 345 |
70 | 5755.619 | 28/1 | ^^M6 +4 oct, vvm7 +4 oct | 350 |
71 | 5837.842 | 29/1 | ^^^m7 +4 oct | 355 |
72 | 5920.065 | 30/1, 31/1 | vM7 +4 oct | 360 |
73 | 6002.288 | 32/1 | P1 +5 oct | 365 |
Approximation to JI
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