User:BudjarnLambeth/Draft related tunings section

From Xenharmonic Wiki
Jump to navigation Jump to search
This user page is editable by any wiki editor.

As a general rule, most users expect their user space to be edited only by themselves, except for minor edits (e.g. maintenance), undoing obviously harmful edits such as vandalism or disruptive editing, and user talk pages.

However, by including this message box, the author of this user page has indicated that this page is open to contributions from other users (e.g. content-related edits).

Introduction

This is a draft of what a standard "related tunings" section might look like on edo pages, using 36edo as an example.


Useful links for working on this:


Which tunings should be listed for any given edo:

  • The edo's pure-octaves tuning
  • 1 to 3 nearby edonoi (eg an edt, an edf, an ed5, an ed7, an ed4/3, anything like that)
  • 1 to 2 nearby ZPIs (or any other "infinite harmonics" optimised tuning other than ZPI)
  • 1 to 2 n-limit WE or n-limit TE tunings, valid examples include:
    • 13-limit WE and 13-limit TE
    • 13-limit WE and 11-limit WE
    • 11-limit TE and 7-limit TE
    • 13-limit TE
    • 11-limit WE
    • Anything else along those kind of lines
  • 0 to 2 subgroup WE or TE tunings, valid examples include:
    • 2.3.7 WE and 2.3.7 TE
    • 2.3.5.11 WE and 2.3.5.11.13 WE
    • 2.3.7 TE and 2.3.7.11 TE
    • 2.5.7.11 TE
    • 2.3.7 WE
    • Anything else along those kind of lines
  • 1 other equal tuning of any kind at all (optional)


Additional guidelines for selecting tunings:

  • In total, 5 to 8 tunings should be listed.
  • The selection of tunings should include at least one stretched tuning and at least one compressed tuning.
  • The most stretched tuning should have +15% to +25% relative error on prime 2, the most compressed should have -15 to -25%, and all the other tunings should cover a wide range of possible tunings in between.



Octave stretch or compression

What follows is a comparison of stretched- and compressed-octave 36edo tunings.

Tuning Step size
(cents)
Prime error (cents) Mapping of primes 2-13 (steps) Stretch
2 3 5 7 11 13
154zpi 33.547 +7.7 +10.2 -1.9 -14.1 +8.5 -12.3 36, 57, 83, 100, 124, 132 +23.1%
36ed513/256 33.427 +3.4 +3.4 -11.9 +7.3 -6.4 +5.3 36, 57, 83, 101, 124, 133 +10.2%
57edt 33.368 +1.2 0 +16.6 +1.3 -13.7 -2.6 36, 57, 84, 101, 124, 133 +3.6%
36edo 33.333 0 -2.0 +13.7 -2.2 +15.3 -7.2 36, 57, 84, 101, 125, 133 0%
13lim WE 33.302 -1.1 -3.7 +11.1 -5.3 +11.4 -11.4 36, 57, 84, 101, 125, 133 -3.3%
11lim WE 33.286 -1.7 -4.7 +9.7 -6.9 +9.4 -13.5 36, 57, 84, 101, 125, 133 -5.1%
156zpi 33.152 -6.5 -12.3 -1.5 +12.7 -7.3 +1.8 36, 57, 84, 102, 125, 134 -19.5%
36ed513/256

Stretching the octave of 36edo by about 3.5 cents results in much improved primes 5 and 11, but a much worse prime 7. This approximates all primes up to 11 within 12 cents. The tuning 36ed513/256 does this.

57edt / 101ed7 / 155zpi / 2.3.7.13 WE-tuned 36edo

If one intends to use both 36edo's vals for 5/1 at once, stretching the octave of 36edo by about 1 cent optimises 36edo for that dual-5 usage, while also making slight improvements to primes 3, 7, 11 and 13. This approximates all primes up to 11 within 17 cents. Four almost identical tunings do this: 57edt, 101ed7, 155zpi, and the 2.3.7.13 subgroup WE tuning of 36edo.

Pure-octaves 36edo

Pure-octaves 36edo approximates all primes up to 11 within 16 cents.

11-limit WE 36edo / 13-limit WE 36edo

Compressing the octave of 36edo by about 2 cents results in much improved primes 5 and 11, but much worse primes 7 and 13. This approximates all primes up to 11 within 10 cents. The 11- and 13-limit WE tunings of 36edo both do this, as do their respective TE tunings.