Bb9 sus chord
Bb9 sus chord for piano with keyboard diagram.
Explanation: The Bb9sus4 is a four-note chord (the four notes are marked in red color in the diagram).
Theory: The Bb9sus4 is an suspended ninth chord with the third replaced by a perfect four. Bb9sus4 is the same as Bb11 without the major third (D).
Notes: Bb - Eb - F - Ab - C