A# Diminished Bass Scale
Bass scale — fretboard 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 Bass, 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 Bass
On bass, locate A# on the A string at fret 1. Use a one-finger-per-fret approach starting from the root and span two to three strings. Keep your fretting hand relaxed and practice shifting between positions cleanly.
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
Begin by playing the A# Diminished scale ascending and descending at 80 BPM using a metronome, one note per beat. Once comfortable, practice in thirds (A#-C#, C-D#) to build intervallic familiarity. Spend 5 minutes daily on this pattern before increasing tempo by 10 BPM.
Experiment with simple two-chord vamps rooted on A# to let the characteristic intervals of the Diminished scale come through clearly.
Bass Tips
On bass, use the A# Diminished scale to build walking bass lines by targeting chord tones on strong beats and using scale tones as approach notes. This is the foundation of functional bass playing.
The A# Diminished scale contains 8 notes (A#, C, C#, D#, E, F#, G, A). Use the interactive fretboard above to explore this scale on Bass with different tunings and fret ranges.
CAGED Positions & Patterns for A# Diminished
The A# Diminished scale can be played in 5 CAGED positions across the fretboard, each based on an open chord shape (C, A, G, E, D). As a 8-note scale, it also lends itself to 3-notes-per-string (3NPS) patterns that facilitate legato playing and diagonal shifting. Use the pattern selector above to isolate each position.