A diminished half-whole scale
- Notes
- A Bb B# C# D# E F# G
- Formula
- 1 b2 #2 3 #4 5 6 b7
- Steps
- H W H W H W H W (W tone, H semitone)
- Also called
- A dominant diminished, A octatonic, starting with a semitone
Eight notes from A up to the next A. Symmetric scales repeat a letter or skip one, so the spelling here keeps each note to a single sharp or flat.
A diminished half-whole on the piano
From A4 to A5, the root in blue-green.
Intervals from A
| Note | Degree | Interval | Semitones |
|---|---|---|---|
| A | 1 | root | 0 |
| Bb | b2 | minor second | 1 |
| B# | #2 | augmented second | 3 |
| C# | 3 | major third | 4 |
| D# | #4 | augmented fourth | 6 |
| E | 5 | perfect fifth | 7 |
| F# | 6 | major sixth | 9 |
| G | b7 | minor seventh | 10 |
A diminished half-whole on the guitar
Standard tuning, high e on top as in tablature, open strings to fret 12. Every dot is a note of the scale; the pattern repeats from fret 12 up.
Chords that fit A diminished half-whole
Every chord of the common types (triads, sus, sixths, sevenths, add9, 7b9, 7#9) whose notes are all in the scale, on each of its notes, spelled as on the chord pages. A 8-note scale has no single set of "the" chords the way a seven-note scale does.
| On | Chords |
|---|---|
| A | A, Am, Adim, A6, Am6, A7, Am7, Am7b5, Adim7, A7b9, A7#9 |
| Bb (A#) | A#dim, A#dim7 |
| B# (C) | C, Cm, Cdim, C6, Cm6, C7, Cm7, Cm7b5, Cdim7, C7b9, C7#9 |
| C# | C#dim, C#dim7 |
| D# (Eb) | Eb, Ebm, D#dim, Eb6, Ebm6, Eb7, Ebm7, D#m7b5, D#dim7, Eb7b9, Eb7#9 |
| E | Edim, Edim7 |
| F# | F#, F#m, F#dim, F#6, F#m6, F#7, F#m7, F#m7b5, F#dim7, F#7b9, Gb7#9 |
| G | Gdim, Gdim7 |
Same notes, different home note
A diminished half-whole uses exactly the same notes as C diminished half-whole, Db diminished whole-half, Eb diminished half-whole, E diminished whole-half, F# diminished half-whole, G diminished whole-half and Bb diminished whole-half. What changes is the note the music keeps returning to, and with it which chord sounds like home.
How A diminished half-whole is built
Eight notes, alternating a semitone and a whole tone, starting with the semitone. Because the pattern repeats every three semitones, the same eight notes are also the half-whole scale on C, Eb and F#; there are only three different diminished scales in all. Jazz players use this one over a dominant seventh with a flat or sharp 9th: A7, A7b9 and A7#9 all sit inside it, as the chord list below shows.
Played some notes and not sure which scale they come from? The scale finder listens to the piano, a MIDI keyboard or the microphone and ranks all 180 scales.
What this page cannot do
- One spelling per scale. the root is spelled the way that needs the fewest sharps and flats.
- Equal temperament only. Blues and many folk traditions bend notes between these pitches, and Arabic and Turkish maqam scales use quarter tones that a piano cannot play.
- The guitar diagram shows standard tuning only and does not suggest fingerings; any note can be played in several places.
- The sound is a simple synthesised tone made in your browser, not a recorded instrument.