A Dim 9 chord — Open D
1 voicing · Open D
Tuning:DADF#AD
Fret 7 position
1 / 1
Chord tones
A
R
C
+3
D#
+6
F#
+9
B
+2
A Dim 9 in other tunings
Dim 9 in other keys — Open D
A Dim 9 in Open D — video lessons
About A Dim 9 in Open D
The A Dim 9 chord contains the notes A, C, D#, F#, B. In Open D tuning (strings: D–A–D–F#–A–D), the chord shapes differ from standard tuning because the open string pitches change. Open D tuning gives an open D major chord across all strings — ideal for slide guitar and Joni Mitchell-style playing. Diagrams above show all playable shapes in this tuning.