16edo: Difference between revisions

Expanded theory section and included sections from the armodue page which I think apply generally
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Approximation to JI: -zeta peak index
 
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== Theory ==
== Theory ==
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 is 27 cents flat of 3/2, flatter than that of [[7edo]] so that it generates an [[2L 5s|antidiatonic]] instead of [[5L 2s|diatonic]] scale, but sharper than [[9edo]]'s fifth, to which it similarly retains the characteristic of being a fifth while being distinctly flat of 3/2. If the fifth is interpreted as 3/2, 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]]. A more accurate restriction is [[mabilic]], which discards the inaccurate mapping of 3 while keeping the fifth as a generator.  


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).
This leads to some confusion in regards to interval names, as what would be major in diatonic now sounds minor; there are several ways to handle this (see in [[#Intervals]]).  


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.
In general, 16edo tends to better approximate the differences between odd [[harmonic]]s than odd harmonics themselves, though it has a [[5/1|5th harmonic]] which is only 11 cents flat, and a [[7/1|7th harmonic]] which is only 6 cents sharp. As such, 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 (i.e. a 3/2 that's 25 cents flat is still recognizable, but a 5/4 that's 25 cents flat loses much of its identity and a 7/4 that's 25 cents flat is completely unrecognizable). In essence, 16edo's 3, 5, and 7 are backwards from 12edo's, with 7 being nearly perfect, 5 being decent, and 3 being distinctly out-of-tune.  


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.  
In terms of higher primes, both 11 and 13 are approximated very flat, with the [[11/8]] not distinguished from [[4/3]], and [[13/8]] not distinguished from [[8/5]]. 16edo represents the no-9 no-15 [[25-odd-limit]] [[consistent]]ly, however.  


12edo's symmetrical diminished seventh chord may be constructed in 16edo by stacking minor thirds.  
Four steps of 16edo gives the 300{{c}} minor third interval shared by [[12edo]] (and other multiples of [[4edo]]), which approximates [[6/5]], and thus tempers out 648/625, the [[diminished comma]]. This means that 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]]. Another possible interpretation for this interval is the 19th harmonic, [[19/16]].
 
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]] tunings, and thus [[slendric]] tunings. 16edo and 15edo also both have three types of seconds and two types of thirds (not including arto/tendo thirds). However, 15edo's fifth is sharp while 16's is flat.  


16edo works as a tuning for [[extraclassical tonality]], due to its ultramajor third of 450 cents.  
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 ===
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=== Composition theory ===
=== Composition theory ===
* [[User:VectorGraphics/16edo theory|Vector's approach]]
* [[User:VectorGraphics/16edo theory|Vector's approach]]
* [[Armodue harmony]]


{{Todo|inline=1| expand }}
{{Todo|inline=1| expand }}
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{{Mavila}}  
{{Mavila}}  


Alternatively, one can use Armodue nine-nominal notation; see [[Armodue theory]]
Alternatively, one can use Armodue nine-nominal notation.


{| class="wikitable center-all"
{| class="wikitable center-all"
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[[:File:16ed2-001.svg|16ed2-001.svg]]
[[:File:16ed2-001.svg|16ed2-001.svg]]
=== Zeta peak index ===
{{ZPI
| zpi = 51
| steps = 15.9443732426877
| step size = 75.2616601314409
| tempered height = 4.191572
| pure height = 3.476281
| integral = 0.812082
| gap = 13.070433
| octave = 1204.18656210305
| consistent = 6
| distinct = 6
}}


== Octave theory ==
== Octave theory ==
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[[File:16-EDO-PIano-Diagram.png|alt=16-EDO-PIano-Diagram.png|748x293px|16-EDO-PIano-Diagram.png]]
[[File:16-EDO-PIano-Diagram.png|alt=16-EDO-PIano-Diagram.png|748x293px|16-EDO-PIano-Diagram.png]]


'''Un-annotated diagram'''
'''Interleaved edos'''


Please explain this image. {{todo|annotate}}
A visualization of 16edo being two interleaved copies of [[8edo]] and four interleaved copies of [[4edo]].


[[File:16edo_wheel_01.png|alt=16edo wheel 01.png|325x325px|16edo wheel 01.png]]
[[File:16edo_wheel_01.png|alt=16edo wheel 01.png|325x325px|16edo wheel 01.png]]


'''Lumatone mapping'''
=== Lumatone mapping ===


See: [[Lumatone mapping for 16edo]]
See: [[Lumatone mapping for 16edo]]