C diminished (half–whole) scale
C diminished (half–whole) is C D♭ E♭ E F♯ G A B♭. Half-whole diminished: eight notes alternating half and whole steps, built from two diminished sevenths and used over dominant sevenths.
- Formula
- 1 ♭2 ♭3 3 ♯4 5 6 ♭7
- Steps
- H W H W H W H W
- Notes
- 8
Notes and degrees
The C diminished (half–whole) scale has eight notes: C D♭ E♭ E F♯ G A B♭. Each degree is named by its distance from the tonic, C.
| Degree | Note | Interval above C | |
|---|---|---|---|
| 1 | P1 | ||
| 2 | m2 | ||
| 3 | m3 | ||
| 4 | M3 | ||
| 5 | A4 | ||
| 6 | P5 | ||
| 7 | M6 | ||
| 8 | m7 |
On the piano
Every key of the scale is lit in its own colour. Click one to hear it.
On the guitar
Every C scale tone on the first twelve frets in standard tuning. The tonic is ringed. Click a dot to hear the note.
What it sounds like
The half-whole diminished scale alternates half and whole steps across eight notes, beginning with a half step from the tonic. Like its partner, it repeats every minor third, so it has only three distinct transpositions. It contains both a major third and a minor third above the root, the flat seventh, the flat ninth, and the sharp ninth, which gives a dense, strongly dominant sound. Over a dominant chord, the flat second and sharp fourth push the color toward altered tension.
Where you hear it
Jazz players use the half-whole diminished scale over dominant seventh chords with altered extensions, placing the tonic on the chord root. On C7, the scale covers the flat ninth, sharp ninth, sharp eleventh, and thirteenth, along with the major third and flat seventh. Because it repeats every minor third, one set of notes fits dominant chords whose roots are a minor third apart. Modern jazz and fusion players favor it for those tense dominant colors.
How it is built
The half-whole diminished scale is the union of two diminished seventh chords, C diminished seventh (C E♭ F♯ A) and D♭ diminished seventh (D♭ E G B♭). On C, it is C D♭ E♭ E F♯ G A B♭. It has no parent mode in the major or minor families and is treated as a separate type. Each of the three octatonic sets can be read as either diminished type, depending on where it starts.
Scales with the same notes
These scales use the same eight pitches as C diminished (half–whole), starting from a different note.
- C♯ diminished (whole–half)
- E♭ diminished (half–whole)
- E diminished (whole–half)
- F♯ diminished (half–whole)
- G diminished (whole–half)
- A diminished (half–whole)
- B♭ diminished (whole–half)
Other C scales
- C major
- C natural minor
- C harmonic minor
- C melodic minor
- C Dorian
- C Phrygian
- C Lydian
- C Mixolydian
- C Locrian
- C major pentatonic
- C minor pentatonic
- C blues
- C whole-tone
- C diminished (whole–half)
- C Phrygian dominant
- C Lydian dominant
- C altered
- C double harmonic major
- C Hungarian minor
- C bebop dominant
How to practise it
Play C half-whole diminished, C D♭ E♭ E F♯ G A B♭, with a drone on C, and hear the half step at the start. Play the diminished seventh arpeggios C E♭ F♯ A and D♭ E G B♭, then move between them through the scale. Over a C7 vamp, improvise with the scale for four bars, landing on the chord tones C, E, G, and B♭, and treat the flat and sharp ninths as passing color.
Further reading
- Chord-Scale Theory Explained: Which Scale Fits Which ChordJazz & Popular Harmony · 7 min
Questions
What are the notes of the C diminished (half–whole) scale?
The C diminished (half–whole) scale is C, D♭, E♭, E, F♯, G, A, B♭. Written ascending it returns to C an octave higher.
What is the formula for the C diminished (half–whole) scale?
The formula is 1 ♭2 ♭3 3 ♯4 5 6 ♭7 measured from the major scale. As steps that is H, W, H, W, H, W, H, W (W is a whole step, H a half step).
What is the half-whole diminished scale?
It is an eight-note scale alternating half and whole steps, starting with a half step. On C it is C D♭ E♭ E F♯ G A B♭. It is one of the two symmetrical diminished scales. Jazz players use it over dominant seventh chords, usually with its tonic on the chord root, to get altered ninths and elevenths.
How do you play half-whole diminished over a dominant chord?
Start the scale on the root of the dominant chord. On C7, the scale C D♭ E♭ E F♯ G A B♭ supplies the flat ninth, sharp ninth, sharp eleventh, and thirteenth. Its third and flat seventh are chord tones, so the chord keeps its identity. The same eight notes fit dominant chords a minor third apart, such as E♭7.
Is half-whole diminished the same as whole-half diminished?
They are two readings of the same three octatonic sets. Whole-half on C, C D E♭ F G♭ A♭ A B, is the same set as half-whole on B. Dominant uses differ in placement: half-whole starts on the chord root, while whole-half starts a half step above it.