Hemififths: Difference between revisions

Cmloegcmluin (talk | contribs)
unchanged interval → unchanged-interval
Discuss possible notation solutions
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The '''hemififths''' temperament tempers out the breedsma, [[2401/2400]], and the hemifamity comma, [[5120/5103]], and as the name suggests, uses a neutral-third generator. '''Hemif''' is the no-5 subgroup version of hemififths.  
'''Hemififths''' is the [[temperament]] [[tempering out]] the breedsma, [[2401/2400]], and the hemifamity comma, [[5120/5103]], and as the name suggests, uses a neutral-third generator. '''Hemif''' is the no-5 subgroup version of hemififths. It is supported by [[41edo|41-]], [[58edo|58-]], and [[99edo|99et]].  


See [[Breedsmic temperaments #Hemififths]] for more technical data.
See [[Breedsmic temperaments #Hemififths]] for more technical data.
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<nowiki>*</nowiki> in 7-limit POTE tuning
<nowiki>*</nowiki> in 7-limit POTE tuning
== Notation ==
Hemififths can be notated in [[neutral circle-of-fifths notation]], in which case 5/4 is represented by a sesqui-augmented second (C-D#+), and 7/4 by a semi-augmented sixth (C-A+). In the 13-limit extension, 11/8 is represented by the semi-augmented fourth (C-F+), and 13/8 by the neutral sixth (C-Ad). This, of course, defies the tradition of tertian harmony. The just major triad on C is C-D#+-G, for example. One may want to adopt an additional module of accidentals such as arrows to represent the comma step. There are two solutions:
# let an arrow represent a bend by the syntonic~septimal comma (17 gensteps, semidiminished second);
# let an arrow represent a bend by the Pythagorean comma (24 gensteps, negative diminished second).
Below is tabulated how to notate the prime harmonics with an arrow representing a syntonic~septimal comma.
{| class="wikitable center-1 center-3"
|+Hemififths nomenclature<br>for selected intervals
! Ratio
! Nominal
! Example
|-
| 3/2
| Perfect fifth
| C-G
|-
| 5/4
| Down major third
| C-vE
|-
| 7/4
| Down minor seventh
| C-vBb
|-
| 11/8
| Semi-augmented fourth
| C-F+
|-
| 13/8
| Neutral sixth
| C-Ad
|}
Below is tabulated how to notate the prime harmonics with an arrow representing a Pythagorean comma.
{| class="wikitable center-1 center-3"
|+Hemififths nomenclature<br>for selected intervals
! Ratio
! Nominal
! Example
|-
| 3/2
| Perfect fifth
| C-G
|-
| 5/4
| Up neutral third
| C-^Ed
|-
| 7/4
| Up semidiminished seventh
| C-^Bdb
|-
| 11/8
| Semi-augmented fourth
| C-F+
|-
| 13/8
| Neutral sixth
| C-Ad
|}


== Chords ==
== Chords ==
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Gencom: [2 11/9; 144/143 196/195 243/242 364/363]
Gencom: [2 11/9; 144/143 196/195 243/242 364/363]


Gencom mapping: [{{val| 1 1 -5 -1 2 4 }}, {{val| 0 2 25 13 5 -1 }}]
Gencom mapping: {{mapping| 1 1 -5 -1 2 4 | 0 2 25 13 5 -1 }}


{| class="wikitable center-all"
{| class="wikitable center-1 center-2"
|-
|-
! ET<br>generator
! Edo<br>generator
! [[eigenmonzo|eigenmonzo<br>(unchanged-interval]])
! [[Eigenmonzo|Eigenmonzo<br>(Unchanged-interval)]]
! generator<br>(¢)
! Generator<br>(¢)
! comments
! Comments
|-
|-
|  
|