16edo: Difference between revisions

Music: Add Bryan Deister's ''Waltz in 16edo'' (2025)
Expanded theory section and included sections from the armodue page which I think apply generally
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== Theory ==
== Theory ==
In general, 16edo tends to better approximate the differences between odd [[harmonic]]s than odd harmonics themselves, though there are exceptions: it has a [[5/1]] which is only eleven cents flat, and a [[7/1]] which is only six cents sharp. Most low harmonics are tuned very flat, but some such as [[21/16|21]]:[[11/8|22]]:[[23/16|23]]:[[3/2|24]]:[[25/16|25]]:[[13/8|26]] are well in tune with each other.  
16edo's fifth is too flat to be a reasonable approximation of 3/2, but still within the range where it can serve the role of a fifth, similarly to 9edo. If it is treated as a diatonic fifth, it generates a scale that is similar to diatonic, but where minor is larger than major, which is called an [[antidiatonic]] scale (with 5 small steps and 2 large steps). It is thus often useful to switch "minor" and "major" from their standard diatonic meanings in interval names (but see below in [[#Intervals]]). If treated as [[3/2]], this fifth produces the [[mavila]] temperament, as stacking it four times produces a [[6/5]] minor third as opposed to the standard [[5/4]] major third found in meantone temperaments. (This tempers out [[135/128]], as that is the difference between 6/5 and 81/64, the interval generated by a stack of 4 untempered fifths. Note that 5/4 is tempered to 32/27.)


The [[3/2|perfect fifth]] of 16edo, so to speak, is 27 cents flat of just, flatter than that of [[7edo]] so that it generates an [[2L 5s|antidiatonic]] instead of [[5L 2s|diatonic]] scale. This befits a tuning of [[mavila]], the [[5-limit]] [[regular temperament|temperament]] that [[tempering out|tempers out]] [[135/128]], such that a stack of four fifths gives a [[6/5]] minor third instead of the familiar [[5/4]] major third as in [[meantone]].  
This minor third is 300 cents (supporting the [[diminished]] temperament), however in this tuning its inaccuracy comes more from the error on the fifth than on the 5/4 major third, which is much closer to (and flat of) just intonation at 375 cents. However, 16edo's best low prime is 7, which is mapped with only 6 cents of error. 13 is also mapped decently accurately (if 12edo's error on 5/4 is acceptable). This contributes to a good tuning of certain [[interseptimal]] intervals, specifically 13/10 and 20/13. As such, 16edo can most reasonably be considered a 2.5.7.13 temperament (2.3.5.7.13, if the mavila fifth is acceptable as a 3/2).


Four steps of 16edo gives the 300{{c}} minor third interval shared by [[12edo]] (and other multiples of [[4edo]]), tempering out 648/625, the [[diminished comma]], and thus the familiar [[diminished seventh chord]] may be built on any scale step with four unique tetrads up to [[octave equivalence]]. The minor third is of course not distinguished from the septimal subminor third, [[7/6]], so [[36/35]] and moreover [[50/49]] are tempered out, making 16edo a possible tuning for [[diminished (temperament)|septimal diminished]].  
7/5 is mapped to the tritone of 600 cents, and 14/13 to the neutral second of 150 cents. 35/32 is mapped to the same interval, and 28/25 is mapped to 225 cents. 
 
16edo can be seen as an approach to tuning that takes advantage of the idea that simpler ratios can be functionally approximated with greater error: by choosing a tuning with greater error on lower primes as opposed to higher ones, one can create a much more consistent feeling than if the highest errors are on higher primes. In essence, 16edo's 3/1, 5/1, and 7/1 are backwards from 12edo's, with 7 being nearly perfect, 5 being decent, and 3 being distinctly out-of-tune.
 
12edo's symmetrical diminished seventh chord may be constructed in 16edo by stacking minor thirds.
 
16edo works as a tuning for [[extraclassical tonality]], due to its ultramajor third of 450 cents.
 
16edo shares several similarities with 15edo. They both share mappings of [[8/7]], [[5/4]], and [[3/2]] in terms of edosteps - in fact, they are both valentine temperaments, and thus slendric temperaments. 16edo and 15edo also both have 3 types of seconds and 2 types of thirds (excluding arto/tendo thirds).
 
However, 15edo's fifth is sharp while 16's is flat.  


=== Odd harmonics ===
=== Odd harmonics ===