A# Diminished Piano Scale
Piano scale diagram
A# Diminished Scale — Notes and Intervals
The A# Diminished scale, also known as the Octatonic scale and Messiaen's Mode of Limited Transposition #2, alternates whole and half steps to create an 8-note symmetrical structure. On Piano, its notes are A#, C, C#, D#, E, F#, G, A. Only three unique diminished scales exist — after three transpositions, the notes repeat. It is the definitive sound of film noir, thrillers, and psychological horror, used by composers from Stravinsky to Hans Zimmer to evoke dread, ambiguity, and mounting tension. Use it over dim7 chords and as a sophisticated tension device over dominant 7ths. Commonly used in Jazz, Film Scores, Classical, Metal. Notable players include Django Reinhardt, Joe Pass, Bela Bartok, Dream Theater. Use over dim7 chords and as a tension device over dominant 7ths. Each diminished scale works over 4 different root notes (every minor 3rd).
Notes: A#, C, C#, D#, E, F#, G, A
Intervals: 1P, 2M, 3m, 4P, 5d, 6m, 6M, 7M
Degrees: 1 2 b3 4 5 b6 7 8
Formula: W-H-W-H-W-H-W-H
Number of notes: 8
Also known as: whole-half diminished
How to Play A# Diminished on Piano
On piano, the A# Diminished scale uses 4 black keys. With several black keys involved, let the thumb naturally fall on white keys where possible. Practice hands separately at first, paying attention to smooth thumb-under transitions.
The A# Diminished scale contains 4 sharps (A#, C#, D#, F#). This scale does not follow a traditional major or minor key signature, so reading from sheet music may require accidentals.
Practice Routine
Set a metronome to 80 BPM and play the A# Diminished scale in groups of four notes, shifting the starting note each repetition. This builds muscle memory across the entire scale range. After a week, try improvising short 4-bar phrases using only these notes.
Experiment with simple two-chord vamps rooted on A# to let the characteristic intervals of the Diminished scale come through clearly.
Piano Tips
On piano, practice the A# Diminished scale hands together in contrary motion (one hand ascending, the other descending). This builds independence and strengthens your awareness of the scale's symmetry.
The A# Diminished scale contains 8 notes (A#, C, C#, D#, E, F#, G, A). Use the interactive piano diagram above to explore this scale on Piano.