A Half-whole Diminished Guitar Scale
Guitar scale in Open A tuning — fretboard diagram
A Half-whole Diminished in Open A — Notes and Intervals
The A Half-whole Diminished scale is a symmetrical scale that is an essential tool for jazz players. On Guitar, the notes are A, Bb, C, C#, D#, E, F#, G. It provides a sophisticated dissonant crunch when played over dominant seventh chords, allowing for complex, high-tension solos that still feel structured. Commonly used in Jazz, Bebop, Fusion, Film Scores. Notable players include Charlie Parker, Joe Pass, Pat Martino, George Benson. Use over dominant 7th chords (7, 7b9, 13b9). The jazz standard for creating structured tension over dominant harmony. Works over 4 roots spaced a minor 3rd apart.
Notes: A, Bb, C, C#, D#, E, F#, G
Intervals: 1P, 2m, 3m, 3M, 4A, 5P, 6M, 7m
Degrees: 1 b2 b3 4 #5 6 7 b8
Formula: H-W-H-W-H-W-H-W
Number of notes: 8
Tuning: Open A (E-A-E-A-C#-E)
Also known as: dominant diminished, messiaen's mode #2
About Open A Tuning
Open A tuning (E-A-E-A-C#-E) produces an A major chord when strummed open. It is structurally identical to Open G tuned up one whole step, delivering a brighter, more tense sound that works particularly well for slide guitar centered on the key of A.
Jimmy Page used Open A with a slide on Led Zeppelin's 'In My Time of Dying' from Physical Graffiti (1975). Rory Gallagher also employed Open A for his raw, energetic slide work. Many players achieve Open A by simply placing a capo at the 2nd fret in Open G tuning, which is why dedicated Open A usage is less commonly discussed. However, without a capo, Open A gives direct access to the open A string resonance and a different feel under the fingers due to the higher tension.
Notable artists: Jimmy Page, Rory Gallagher, Delta blues players
Best for: Slide guitar in the key of A, blues playing, and situations where you need the brightness of Open G tuned up without a capo
Musical Character
The inverse of the whole-half diminished — starts with a half step. This version is the standard jazz choice over dominant 7th chords, providing a sophisticated 'crunch' that resolves beautifully.
Chord Progressions Using This Scale
- I – ♯I°7 – ii – V (Diminished Cliché)Jazz / Soul — Nostalgic & Vintage
Explore This Scale in Other Tunings
- A Half-whole Diminished in Standard Tuning
- A Half-whole Diminished in Drop D
- A Half-whole Diminished in DADGAD
- A Half-whole Diminished in Open G
- A Half-whole Diminished in Baritone (B Standard)
- A Half-whole Diminished in 7-string
- A Half-whole Diminished in 8-string
- A Half-whole Diminished in Drop C
- A Half-whole Diminished in Drop B
- A Half-whole Diminished in Open D
- A Half-whole Diminished in Half Step Down
- A Half-whole Diminished in Open E
- A Half-whole Diminished in Double Drop D
- A Half-whole Diminished in Open C