The A9 chord contains the notes A, C#, E, G and B. It is produced by taking the 1 (root), 3, 5, b7 and 9 of the A Major scale. The 9th note of the scale (B) is the same as the 2nd note, but we refer to it as a 9, as this implies that the chord is a dominant 7 chord (1, 3, 5, 7) with a 9 included.
The 9th chord is a very popular guitar chord in Jazz, Funk and Blues. It is in many ways, the go-to ‘funk’ chord. The 9th chord can often be substituted for a dominant 7 chord. Let’s take an example chord progression:
Try playing this chord progression. After a while, try substituting the A7 chord for an A9 chord. You should hear that the chord progression sounds very similar, but the inclusion of the A9 chord gives the chord progression a jazzy sound.
Because the A7 chord is a very popular guitar chord, the A9 chord is also very popular. It is most commonly played with the root note on the 12th fret of the 5th string (2nd shape in the picture below).
10 Ways To Play The A9 Chord
If you’ve come to this page just to view some chord diagrams for A9, here they are.
Some Quick A9 Chord Theory
- The A9 chord contains the notes A, C# E, G and B.
- The A9 chord is produced by taking the 1 (root), 3, 5, b7 and 9 of the A Major scale.
- The 9th note of the A Major scale (B) is the same as the 2nd note of the scale.
- The A9 can be used as a substitute for the A7 chord.
- The A9 is essentially an A dominant 7 chord with an added 9.
- The A mixolydian mode can be used when soloing over the A9 chord.