User:Zhenlige/Chromatic notation

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This page introduces a proposed notation system centering the 5L 7s chromatic scale. This system is suitable for temperaments with consonant intervals far away in the chain of fifths, such as schismatic. Adding more naturals is usually unnecessary, since the 12-comma is much smaller than the limma in JI. For the meantone chromatic scale 7L 5s, there are two approches to use this system, in anology to using the standard notation system for the antidiatonic scale.

Intervals

The degrees are named as 0-indexed numbers of “sem”, which stands for “semitone”, referring to the chromatic step. 12edo diatonic interval names can also be used for representing degrees, with A4 and d5 merged into “tritone”. The 5L 7s major, minor, augmented and diminished are renamed to wide (W), narrow (n), super (S) and sub (s) respectively, to avoid ambiguity. Note that diatonic major is always wide and diatonic minor is always narrow, which also applies to fourths and fifths as if they were named the same as other intervals. Mid or neutral degrees should be abbreviated as “m” or “~” to avoid confusion with “n” which stands for narrow.

Chromatic interval degrees
Interval Abbrev. Steps 29edo
tuning
(steps)
Equivalent
diatonic
degree
Approximate ratios
Degree Degree name
from 12edo diatonic
Quality L s schismatic additional
in garibaldi
Unison
0-tone
0-sem
Unison Perfect P0s / P1 0 0 0 P1 1/1
Semitone
Sem / 1-sem
Minor second Narrow n1s / nm2 0 1 2 m2 135/128, 256/243 21/20
Wide W1s / Wm2 1 0 3 A1 16/15 15/14
Tone / 1-tone
2-sem
Major second Narrow n2s / nM2 0 2 4 d3 10/9
Wide W2s / WM2 1 1 5 M2 9/8
3-sem Minor third Narrow n3s / nm3 1 2 7 m3 32/27
Wide W3s / Wm3 2 1 8 A2 6/5
Ditone / 2-tone
4-sem
Major third Narrow n4s / nM3 1 3 9 d4 5/4 56/45
Wide W4s / WM3 2 2 10 M3 81/64 80/63, 63/50
5-sem Fourth Perfect P5s / P4 2 3 12 P4 4/3
Super S5s / S4 3 2 13 A3 27/20
Tritone / 3-tone
6-sem
Tritone Narrow n6s / nT 2 4 14 d5 45/32 7/5
Wide W6s / WT 3 3 15 A4 64/45 10/7
7-sem Fifth Sub s7s / s5 2 5 16 d6 40/27
Perfect P7s / P5 3 4 17 P5 3/2
Tetratone / 4-tone
8-sem
Minor sixth Narrow n8s / nm6 3 5 19 m6 128/81 63/40, 100/63
Wide W8s / Wm6 4 4 20 A5 8/5 45/28
9-sem Major sixth Narrow n9s / nM6 3 6 21 d7 5/3
Wide W9s / WM6 4 5 22 M6 27/16
Pentatone / 5-tone
10-sem
Minor seventh Narrow n10s / nm7 4 6 24 m7 16/9
Wide W10s / Wm7 5 5 25 A6 9/5
11-sem Major seventh Narrow n11s / nM7 4 7 26 d8 15/8 28/15
Wide W11s / WM7 5 6 27 M7 243/128, 256/135 40/21
Hexatone / 6-tone
12-sem
Octave Perfect P12s / P8 5 7 29 P8 2/1

The 12edo diatonic based interval names along the chain of fifths is P1-P5-WM2-WM6-WM3-WM7-WT-Wm2-Wm6-Wm3-Wm7-S4-S1-S5-SM2-… with the quality goes as perfect - wide major - wide minor - super - super major - super minor - double super … .

Note names

Latin letters ABCDEFG and Greek letters αβγδε are used. Latin letters represent the same notes as diatonic. Each Greek letter represents the note a diatonic chroma below the note marked with the corresponding Latin letter. Ups and downs are used for altering 12-commas.

Chromatic Diatonic
D D
ε E♭
D♯
E E
F F
γ G♭
F♯
G G
α A♭
G♯
A A
β B♭
A♯
B B
C C
δ D♭
C♯
D D

Staves

A 9-lined staff is used. To improve readability, the lines alter between thin and thick. The first and last lines are thick. Only C-clef is used. C is always on a thick line. For the standard clef, the notes on the lines are EγαβCDEγα.

Applications

The chromatic notation is useful for notating temperaments that require many fifths to get some primes, making diatonic notation very unintuitive, or that have interdiatonic degrees such as the half octave.

Interval mappings in some temperaments
(12edo diatonic based names)
Interval Ponta Cassandra Leapday Diaschismic
5/4 nM3 nM3 Sm3 ~M3
7/4 3SM6 sm7 SM6 1/2-sm7
11/8 7s5 2S4 S4 1/2-sT
13/8 Sm6 Wm6 1/2-sM6
17/16 2S1 ~m2
Interval mappings in some temperaments
(n-sem names)
Interval Ponta Cassandra Leapday Diaschismic
5/4 n4s n4s S3s ~4s
7/4 3S9s s10s S9s 1/2-s10s
11/8 7s7s 2S5s S5s 1/2-s6s
13/8 S8s W8s 1/2-s9s
17/16 2S0s ~1s