B flat ninth guitar chord (Bb9)
Also written A#9 (A sharp ninth)
A ninth chord adds a ninth to the seventh chord. A rich, groovy sound, typical of funk, soul and blues.
Positions and fingerings
Position 1 open position
Position 2 fret 6
× muted string · o open string · numbers: fingers (1 index, 2 middle, 3 ring, 4 pinky)
Chord notes
| Note | Interval |
|---|---|
| B♭ (B flat) | root |
| D | major third |
| F | perfect fifth |
| A♭ (A flat) | minor seventh |
| C | major ninth |
Formula: 1 – 3 – 5 – b7 – 9 · B♭ – D – F – A♭ – C
A progression with this chord
The basis of blues and funk: the ninth chord on the first degree, then on the fourth.