User:BudjarnLambeth/Sandbox2

From Xenharmonic Wiki
Jump to navigation Jump to search

Title1

Octave stretch or compression

99edo's approximations of harmonics 3, 5, and 7 can all be improved if slightly compressing the octave is acceptable, using tunings such as 157edt or 256ed6. 157edt is especially performant if the 13-limit of the 99ef val is intended, but the 7-limit part is overcompressed, for which the milder 256ed6 is a better choice. If the 13-limit patent val is intended, then little to no compression, or even stretch, might be serviceable.

What follows is a comparison of stretched- and compressed-octave 99edo tunings.

567zpi
  • Step size: 12.138 ¢, octave size: 1201.66 ¢

Stretching the octave of 99edo by around 1.5 ¢ results in improved primes 11, 13, 17, and 19, but worse primes 2, 3, 5 and 7. This approximates all harmonics up to 16 within 5.54 ¢. The tuning 567zpi does this.

Approximation of harmonics in 567zpi
Harmonic 2 3 4 5 6 7 8 9 10 11 12
Error Absolute (¢) +1.66 +3.71 +3.32 +5.43 +5.37 +5.54 +4.99 -4.72 -5.05 -0.12 -5.10
Relative (%) +13.7 +30.6 +27.4 +44.7 +44.3 +45.6 +41.1 -38.9 -41.6 -1.0 -42.0
Step 99 157 198 230 256 278 297 313 328 342 354
Approximation of harmonics in 567zpi (continued)
Harmonic 13 14 15 16 17 18 19 20 21 22 23 24
Error Absolute (¢) +1.98 -4.94 -3.00 -5.49 -1.20 -3.05 +0.45 -3.39 -2.89 +1.54 -2.59 -3.44
Relative (%) +16.3 -40.7 -24.7 -45.2 -9.9 -25.2 +3.7 -27.9 -23.8 +12.7 -21.3 -28.3
Step 366 376 386 395 404 412 420 427 434 441 447 453
99et, 13-limit WE tuning
  • Step size: 12.123 ¢, octave size: 1200.18 ¢

Stretching the octave of 99edo by around a fifth of a cent results in improved primes 11 and 13, but worse primes 2, 3, 5 and 7. This approximates all harmonics up to 16 within 5.25 ¢. Its 13-limit WE tuning and 13-limit TE tuning both do this.

Approximation of harmonics in 99et, 13-limit WE tuning
Harmonic 2 3 4 5 6 7 8 9 10 11 12
Error Absolute (¢) +0.18 +1.36 +0.35 +1.98 +1.53 +1.37 +0.53 +2.71 +2.15 -5.25 +1.71
Relative (%) +1.5 +11.2 +2.9 +16.3 +12.6 +11.3 +4.4 +22.4 +17.8 -43.3 +14.1
Step 99 157 198 230 256 278 297 314 329 342 355
Approximation of harmonics in 99et, 13-limit WE tuning (continued)
Harmonic 13 14 15 16 17 18 19 20 21 22 23 24
Error Absolute (¢) -3.51 +1.55 +3.33 +0.71 +4.86 +2.89 -5.85 +2.33 +2.72 -5.07 +2.83 +1.89
Relative (%) -29.0 +12.7 +27.5 +5.8 +40.1 +23.8 -48.3 +19.2 +22.5 -41.9 +23.3 +15.6
Step 366 377 387 396 405 413 420 428 435 441 448 454
99edo
  • Step size: 12.121 ¢, octave size: 1200.00 ¢

Pure-octaves 99edo approximates all harmonics up to 16 within 5.86 ¢.

Approximation of harmonics in 99edo
Harmonic 2 3 4 5 6 7 8 9 10 11 12
Error Absolute (¢) +0.00 +1.08 +0.00 +1.57 +1.08 +0.87 +0.00 +2.15 +1.57 -5.86 +1.08
Relative (%) +0.0 +8.9 +0.0 +12.9 +8.9 +7.2 +0.0 +17.7 +12.9 -48.4 +8.9
Steps
(reduced)
99
(0)
157
(58)
198
(0)
230
(32)
256
(58)
278
(80)
297
(0)
314
(17)
329
(32)
342
(45)
355
(58)
Approximation of harmonics in 99edo (continued)
Harmonic 13 14 15 16 17 18 19 20 21 22 23 24
Error Absolute (¢) -4.16 +0.87 +2.64 +0.00 +4.14 +2.15 +5.52 +1.57 +1.95 -5.86 +2.03 +1.08
Relative (%) -34.4 +7.2 +21.8 +0.0 +34.1 +17.7 +45.5 +12.9 +16.1 -48.4 +16.7 +8.9
Steps
(reduced)
366
(69)
377
(80)
387
(90)
396
(0)
405
(9)
413
(17)
421
(25)
428
(32)
435
(39)
441
(45)
448
(52)
454
(58)
99et, 7-limit WE tuning / 256ed6
  • Step size: 12.117 ¢, octave size: 1199.58 ¢

Compressing the octave of 99edo by around 0.6 ¢ results in improved primes 3, 5, 7 and 11, but worse primes 2 and 13. This approximates all harmonics up to 16 within 5.71 ¢. Its 7-limit WE tuning and 7-limit TE tuning both do this. So does the tuning 256ed6 whose octave is identical within a thousandth of a cent.

Approximation of harmonics in 99et, 7-limit WE tuning
Harmonic 2 3 4 5 6 7 8 9 10 11 12
Error Absolute (¢) -0.42 +0.41 -0.83 +0.60 -0.00 -0.30 -1.25 +0.83 +0.18 +4.81 -0.42
Relative (%) -3.4 +3.4 -6.9 +4.9 -0.0 -2.5 -10.3 +6.8 +1.5 +39.7 -3.5
Step 99 157 198 230 256 278 297 314 329 343 355
Approximation of harmonics in 99et, 7-limit WE tuning (continued)
Harmonic 13 14 15 16 17 18 19 20 21 22 23 24
Error Absolute (¢) -5.71 -0.72 +1.01 -1.67 +2.43 +0.41 +3.74 -0.24 +0.11 +4.40 +0.14 -0.84
Relative (%) -47.1 -5.9 +8.3 -13.8 +20.1 +3.4 +30.9 -2.0 +0.9 +36.3 +1.2 -6.9
Step 366 377 387 396 405 413 421 428 435 442 448 454
568zpi
  • Step size: 12.115 ¢, octave size: 1199.39 ¢

Compressing the octave of 99edo by around 0.4 ¢ results in improved primes 3, 5, 7 and 11, but worse primes 2 and 13. This approximates all harmonics up to 16 within 5.68 ¢. The tuning 568zpi does this.

Approximation of harmonics in 568zpi
Harmonic 2 3 4 5 6 7 8 9 10 11 12
Error Absolute (¢) -0.61 +0.10 -1.23 +0.14 -0.52 -0.86 -1.84 +0.20 -0.48 +4.13 -1.13
Relative (%) -5.1 +0.8 -10.2 +1.1 -4.3 -7.1 -15.2 +1.7 -4.0 +34.1 -9.3
Step 99 157 198 230 256 278 297 314 329 343 355
Approximation of harmonics in 568zpi (continued)
Harmonic 13 14 15 16 17 18 19 20 21 22 23 24
Error Absolute (¢) +5.68 -1.47 +0.24 -2.46 +1.62 -0.42 +2.90 -1.09 -0.76 +3.51 -0.75 -1.75
Relative (%) +46.9 -12.1 +2.0 -20.3 +13.4 -3.4 +24.0 -9.0 -6.2 +29.0 -6.2 -14.4
Step 367 377 387 396 405 413 421 428 435 442 448 454
157edt / 230ed5
  • Step size: 12.114 ¢, octave size: 1199.32 ¢

Compressing the octave of 99edo by around 0.3 ¢ results in improved primes 3, 5, 7 and 11, but worse primes 2 and 13. This approximates all harmonics up to 16 within 5.44 ¢. The tuning 157edt does this. So does 230ed5 whose octave is identical within a hundredth of a cent.

Approximation of harmonics in 157edt
Harmonic 2 3 4 5 6 7 8 9 10 11 12
Error Absolute (¢) -0.68 +0.00 -1.36 -0.01 -0.68 -1.03 -2.03 +0.00 -0.69 +3.91 -1.36
Relative (%) -5.6 +0.0 -11.2 -0.1 -5.6 -8.5 -16.8 +0.0 -5.7 +32.3 -11.2
Steps
(reduced)
99
(99)
157
(0)
198
(41)
230
(73)
256
(99)
278
(121)
297
(140)
314
(0)
329
(15)
343
(29)
355
(41)
Approximation of harmonics in 157edt (continued)
Harmonic 13 14 15 16 17 18 19 20 21 22 23 24
Error Absolute (¢) +5.44 -1.71 -0.01 -2.71 +1.36 -0.68 +2.63 -1.37 -1.03 +3.23 -1.04 -2.03
Relative (%) +44.9 -14.1 -0.1 -22.4 +11.2 -5.6 +21.7 -11.3 -8.5 +26.7 -8.6 -16.8
Steps
(reduced)
367
(53)
377
(63)
387
(73)
396
(82)
405
(91)
413
(99)
421
(107)
428
(114)
435
(121)
442
(128)
448
(134)
454
(140)

Title2

Placeholder