12edo: Difference between revisions

== Octave stretch or compression ==

; [[WE|12et, 7-limit WE tuning]]  

* Step size: 99.664{{c}}, octave size: 1196.0{{c}}

Compressing the octave of 12edo by 4{{c}} results in much improved primes 5, 7 and 11, but a much worse prime 3. Its 7-limit WE tuning and 7-limit [[TE]] tuning both do this. [[40ed10]] does this as well. An argument could be made that such tunings [[7-limit|harmonies involving the 7th harmonic]] to regular old 12edo without even needing to add any new notes to the octave. This adds in brand new harmonic possibilities without breaking any common 12-tone music theory.

; [[zpi|34zpi]]  

* Step size: 99.807{{c}}, octave size: 1197.7{{c}}

Compressing the octave of 12edo by around 2{{c}} results in improved primes 5 and 7, but a worse prime 3. The tuning 34zpi does this. It might be a good tuning for 5-limit [[meantone]], for composers seeking more pure thirds and sixths than regular 12edo. It would be well suited for playing classic pieces written for [[historical temperaments]], as well as being well suited to playing simultaneously with other instruments or voices that use [[just intonation]].

; [[WE|12et, 5-limit WE tuning]]  

* Step size: 99.868{{c}}, octave size: 1198.4{{c}}

Compressing the octave of 12edo by around 1{{c}} results in slightly improved primes 5 and 7, but a slightly prime 3. Its 5-limit WE tuning and 5-limit [[TE]] tuning both do this. This has the same benefits and drawbacks as 34zpi, but both are less intense here compared to 34zpi.

; 12edo

* Step size: 100.000{{c}}, octave size: 1200.0{{c}}  

Pure-octaves 12edo performs well on harmonics 2, 3 and 5 but poorly on harmonics 7, 11 and 13 compared to other edos with a similar number of notes per octave.

; [[31ed6]]  

* Step size: 100.063{{c}}, octave size: 1200.8{{c}}

Stretching the octave of 12edo by a little less than 1{{c}} results in an improved prime 3, but worse prime 5. This loosely resembles the stretched-octave tunings commonly used on pianos. It may better match the [[timbre|slightly inharmonic partials]] of some string instruments. The tuning 31ed6 does this.

; [[19edt]]  

* Step size: 101.103{{c}}, octave size: 1201.2{{c}}

Stretching the octave of 12edo by a little more than 1{{c}} results in an improved prime 3, but worse prime 5. It may better match the [[timbre|slightly inharmonic partials]] of some string instruments. The tuning 19edt does this.

; [[7edf]]  

* Step size: 100.3{{c}}, octave size: 1203.35{{c}}

Stretching the octave of 12edo by around 3{{c}} results in improved primes 3 and 13, but much worse primes 5 and 7. This has similar benefits and drawbacks to [[Pythagorean]] tuning. Most modern music probably won't sound very good here because of the off 5th harmonic. The tuning 7edf does this.

== Scales ==