Heptatonic

A scale with seven tones per octave is called a heptatonic scale.

[from John Chalmers, Divisions of the Tetrachord]

. . . . . . . . . . . . . . . . . . . . . . . . . . . .

The most typical examples of heptatonic scales are the usual diatonic major and minor scales, composed of 5 Large (L) steps and 2 small (s) steps (which in this case are synonymous with tone and semitone, respectively. The minor scales are given in their "natural minor" form:

  L  s  L  L  s  L  L     L  L  s  L  L  L  s

A#-minor                C#-major
A# B# C# D# E# F# G#    C# D# E# F# G# A# B#

D#-minor                F#-major
D# E# F# G# A# B C#     F# G# A# B C# D# E# 

G#-minor                B-major
G# A# B C# D# E  F#     B C# D# E  F# G# A#     

C#-minor                E-major
C# D# E F# G# A B       E F# G# A B C# D# 

F#-minor                A-major
F# G# A B C# D E        A B C# D E F# G# 

B-minor                 D-major
B C# D E F# G A         D E F# G A B C# 

E-minor                 G-major
E F# G A B C D          G A B C D E F# 

A-minor                 C-major
A B C D E F G           C D E F G A B

D-minor                 F-major
D E F G A Bb C          F G A Bb C D E

G-minor                 Bb-major
G A Bb CD Eb F          Bb C D Eb F G A 

C-minor                 Eb-major
C D Eb F G Ab Bb        F G Ab Bb C D Eb 

F-minor                 Ab-major
F G Ab Bb C Db Eb       Ab Bb C Db Eb F G 

Bb-minor                Db-major
Bb C Db Eb F Gb Ab      Db Eb F Gb  Ab Bb C 

Eb-minor                Gb-major
Eb F Gb Ab Bb Cb Db     Gb  Ab Bb Cb Db Eb F 

Ab-minor                Cb-major
Ab Bb Cb Db Eb Fb Gb    Cb Db Eb Fb  Gb  Ab Bb 


These scales may be tuned in a wide variety of different tunings, which is one fact which helps to account for their great popularity.

These diatonic scales are recorded unambiguously in ancient Greek music-theory texts, almost always in Pythagorean tuning.

As the diatonic scales developed in medieval Europe they were expected to be tuned according to one of the various members of the meantone family of temperaments.

Today the diatonic scales are most commonly presented in 12edo. Note that in 12edo, 3 pairs of keys in each mode (major and minor) are enharmonically equivalent: Bb/A#, Eb/D#, and Ab/G# minor, and Db/C#, Gb/F#, and Cb/B major.


There are probably thousands of other heptatonic scales, 7 being one of the most important numbers of the Miller Limit.

[from Joe Monzo, JustMusic: A New Harmony]

---

updated:

2002.11.4 -- added table of major and minor scales

---

(to download a zip file of the entire Dictionary, click here)

For many more diagrams and explanations of historical tunings, see my book. If you don't understand my theory or the terms I've used, start here

I welcome feedback about this webpage: corrections, improvements, good links. Let me know if you don't understand something. return to the Microtonal Dictionary index return to my home page return to the Sonic Arts home page