The B-flat dominant seventh sharp ninth chord (abbreviated "Bb7(#9) chord") is a five-note chord consisting of the notes B, D, F, A, and C. The chord is formed by adding an augmented ninth to a B-flat dominant seventh chord.

In practice, the fifth (F) is often omitted from the Bb7(#9) chord because it's not always possible to play all notes simultaneously.

Name
B-flat dominant seventh sharp ninth chord
Synonym
B-flat dominant sharp ninth chord
Notes
B D F A C
Intervals
1 3 5 7 9
Chord symbol
B7(#9)
Alternative symbol
B7#9
Type
Pentad (five-note chord)

Bb7(#9) chord on piano

Bb7(#9) chord on guitar

Bb7(#9) chord on ukulele

Bb7(#9) chord on the staff