Golden magic

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Golden magic is a tuning of magic temperament where the 19 tone, 22 tone and 41 tone MOS's have step size ratios equal to the golden ratio. It is very closely approximated by 104edo and 167edo. The generator of golden magic is roughly 380.819 cents.

Scale

Golden magic approximates simple intervals in the 2,3,7,11 subgroup very closely and 5 somewhat less closely (in fact 5 has the highest error of any identity in the 11 limit). Here's the 41 tone MOS with a JI detempering in the 2,3,7,11 subgroup:

Scale Degree Ratio Golden Magic Detempered Error Color Notation
0 1/1 0.000 0.000 0.000 w1
1 49/48 35.563 35.697 -0.134 zz2
2 33/32 57.543 53.273 4.270 1o1
3 81/77 93.106 87.676 5.430 1ur1
4 77/72 115.085 116.234 -1.149 1oz2
5 12/11 150.649 150.637 0.012 1u2
6 54/49 172.628 168.213 4.415 rr1
7 9/8 208.191 203.910 4.281 w2
8 8/7 230.171 231.174 -1.004 r2
9 7/6 265.734 266.871 -1.137 z3
10 33/28 287.713 284.447 3.266 1or2
11 77/64 323.276 320.144 3.133 1oz3
12 11/9 345.256 347.408 -2.152 1o3
13 96/77 380.819 381.811 -0.992 1ur3
14 14/11 416.382 417.508 -1.126 1uz4
15 9/7 438.362 435.084 3.278 r3
16 21/16 473.925 470.781 3.144 z4
17 4/3 495.904 498.045 -2.141 w4
18 49/36 531.468 533.742 -2.274 zz5
19 11/8 553.447 551.318 2.129 1o4
20 108/77 589.010 585.721 3.289 1ur4
21 77/54 610.990 614.279 -3.289 1oz5
22 16/11 646.553 648.682 -2.129 1u5
23 72/49 668.532 666.258 2.274 rr4
24 3/2 704.096 701.955 2.141 w5
25 32/21 726.075 729.219 -3.144 r5
26 14/9 761.638 764.916 -3.278 z6
27 11/7 783.618 782.492 1.126 1or5
28 77/48 819.181 818.189 0.992 1oz6
29 18/11 854.744 852.592 2.152 1u6
30 128/77 876.724 879.856 -3.133 1ur6
31 56/33 912.287 915.553 -3.266 1uz7
32 12/7 934.266 933.129 1.137 r6
33 7/4 969.829 968.826 1.004 z7
34 16/9 991.809 996.090 -4.281 w7
35 49/27 1027.372 1031.787 -4.415 zz8
36 11/6 1049.351 1049.363 -0.012 1o7
37 144/77 1084.915 1083.766 1.149 1ur7
38 154/81 1106.894 1112.324 -5.430 1oz8
39 64/33 1142.457 1146.727 -4.270 1u8
40 96/49 1164.437 1164.303 0.134 rr7
41 2/1 1200.000 1200.000 0.000 w8

The highest error of any interval in the 1,3,7,9,11 tonality diamond is 9/8, which is 4.281 cents sharp, and the lowest error is 0.012 cents, for 11/6. Golden magic tempers out the Saluzo comma as well as the Saquinzo comma. Furthermore, five generators of golden magic equal the perfect fifth in Peppermint-24, and golden magic can be construed as a close rank 2 approximation of Peppermint, with the quasi-diesis being 57.543 cents.

The extension of golden magic to the full 11 limit also tempers out the Laquinyo comma, the Ruyoyo comma, the Zozoyo comma, and the Zotriyo comma.

Golden magic can be extended to the 13 limit by tempering out the Tholuluzo comma and the Thoquadzo comma. The 63 tone golden magic MOS has a copy of the 9 tone praveensmic MOS as well as the 18 tone 3-MOS.

Golden Kite Guitar

A guitar fretting very similar to the Kite guitar is possible with the 41 tone golden magic MOS -- frets can be set to every other note of the 41 tone MOS. To make 11 limit chord fingerings more ergonomic across the neck (since 11 limit intervals require relatively huge stretches near the nut on a Kite guitar), one can fret the guitar to the full 41 tone MOS up to the twelfth fret and transition to 2\41 increments beyond that.

A tuning that consists of alternating downmajor thirds at 380.819c and upmajor thirds at 438.362c is recommended as it makes the stretches needed to play 11 limit chords on a Kite guitar more manageable.