Guitar chords in the key of G# or Ab:
Ab Bbm Cm C# Eb Fm Gdim

Chord Ab9-5 (10th fret) notes: Ebb, Ab, C, Gb, Bb and Ebb. (Ebb is E double flat or D).

This chord is played by placing a barre on fret ten with your index finger.

Ab(G#) dominant 9th b5 guitar chord's alternative names: Ab7(b5,9), Ab9b5.

Steps: 1-3-b5-b7-9.
1(G#/Ab), 3(C), b5(D/Ebb), b7(F#/Gb), 9(A#/Bb).