AKA: B7(add9), B7/9, B9, B Dominant 9, B Dominant ninth, B Ninth
B9 Accordion Chord Chart
9th Chords
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.
Notes:
B, D#, F#, A, C#
Intervals:
R, 3°, 5°, m7°, 9°
Left hand:
B + BM + F#m
(C♭ + C♭M + G♭m)
Fingering:
4 + 3 + 2
Hello
Thanks for this incredible job. Please, is there a way how to play b7+9? Trying to learn The Yardbird Suite. Here it’s coming right after c.
Hi!
Yes. On a standard Stradella bass accordion, a B7#9 (often written B7+9) can be approximated by combining B bass + B7 chord + D major chord or another way is to play B7 chord + Bm chord (the root in both cases is optional).
The chord tones are B–D#–F#–A–D (the D is the sharp 9, enharmonically C##).
It is important to understand how this sounds on the instrument. Because the accordion’s Stradella bass system has a limited pitch range and fixed chord voicings, the sharp ninth in B7#9 is not placed an octave higher as it would be in a typical jazz voicing. Instead, it sounds within the same octave as the other chord tones.
As a result, the #9 does not function as a clear upper extension, but ends up sounding just like a minor third. This creates a dense cluster inside a single octave rather than a spaced jazz chord.
Hope this helps!