Finger Positions

Root Note A

Name A over D#

Intervals 1P-3M-5P-7m-9A-11A

Relative Minor F#m

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

Aliases A7#9#11, A7b5#9, A7#9b5

How to play the A7#9b5/D# Chord

The A7#9b5/D# 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 D# is built using the 1P, 3M, 5P, 7m, 9A, 11A intervals. In the key of A Major, this chord functions as the I chord.

Common Progressions

In music composition, the A7#9b5/D# chord is often used to create tension or resolution.

I-V-vi-IV

A → E → F#m → D

vi-IV-I-V

F#m → D → A → E

The Diatonic Family

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

Triads

A Bm C#m D E F#m G#dim

7ths

Amaj7 Bm7 C#m7 Dmaj7 E7 F#m7 G#m7b5

Scale Compatibility

View All Scales

Hungarian Major Flamenco Half-Whole Diminished Composite Blues Messiaen's Mode #3 Chromatic

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

Acoustic & Digital Analysis

Digital footprint of the A7#9b5/D# chord for MIDI programming and synthesizer sound design.

MIDI Numbers 69, 61, 64, 67, 60, 63

Frequencies (Hz)

440, 277.1826309768721, 329.6275569128699, 391.99543598174927, 261.6255653005986, 311.1269837220809