Finger Positions

Diagram unavailable.

Root Note A#

Name A# over C#

Intervals 1P-3M-5d-7m-9M

Relative Minor Gm

Notes C#, A#, D, E, G#, C

Aliases A#9b5

How to play the A#9b5/C# Chord

The A#9b5/C# is a fundamental dominant chord in guitar music. To play this chord correctly, ensure your fingers are placed precisely on the frets indicated in the diagram above.

Music Theory Analysis

From a theoretical perspective, the A# over C# is built using the 1P, 3M, 5d, 7m, 9M intervals. In the key of A# Major, this chord functions as the I chord.

Common Progressions

In music composition, the A#9b5/C# chord is often used to create tension or resolution.

I-V-vi-IV

A# → F → Gm → D#

vi-IV-I-V

Gm → D# → A# → F

The Diatonic Family

Understanding the "family" of chords that belong to A# helps with transposition and ear training.

Triads

A# Cm Dm D# F Gm Adim

7ths

A#maj7 Cm7 Dm7 D#maj7 F7 Gm7 Am7b5

Scale Compatibility

View All Scales

Prometheus Whole Tone Locrian Major Lydian Dominant Leading Whole Tone Lydian Minor Messiaen's Mode #6 Composite Blues Messiaen's Mode #3 Chromatic

* 10 scales found containing the notes C#, A#, D, E, G#, C.

Acoustic & Digital Analysis

Digital footprint of the A#9b5/C# chord for MIDI programming and synthesizer sound design.

MIDI Numbers 61, 70, 62, 64, 68, 60

Frequencies (Hz)

277.1826309768721, 466.1637615180899, 293.6647679174076, 329.6275569128699, 415.3046975799451, 261.6255653005986