AKA: C7(add9), C7/9, C9, C Dominant 9, C Dominant ninth, C Ninth
C9 Accordion Chord Chart
A 9th chord, as extended chord, is a type of major chord that includes the minor 7th and the 9th intervals or if you prefer, it’s a dominant 7th chord with a 9th.
To play a 9th chord, you will typically use a Root, a major 3rd, a perfect 5th, a minor 7th, and a major 9th notes of the major scale.
The 9th chord is a common chord in jazz and other styles of music that use extended chords.
9th Chords on Accordion
On Stradella bass system accordion, you can play 9th chords by combining a root note and its Major chord, plus the minor chord built on the 5th degree of the Major scale, which is located right above the row of the root. The Major chord has the root, the 3rd and the 5th while the minor chord adds the minor 7th and the 9th.
For example, combining C Major and G minor, you get a C9 (C, E, G, Bb, D) because C Maj (C, E, G) has the root, 3rd and 5th, which are C, E, G and G min (G, Bb, D) adds the 7th and 9th, which are Bb and D.
You could also play just the root and the minor chord omitting the Major chord. In this way you lose the 3rd but it’s not an issue because it doesn’t add any tension. Obviously the chord will be less rich but it will still sound as a 9th chord.
C, E, G, B♭, D
R, 3°, 5°, m7°, 9°
C + CM + Gm
4 + 3 + 2