B♭ Altered Dominant
Bb7alt · Root
Every chord tone stacked from the root up.
Click keys to experiment with the chord
B♭ – D – A♭ – C♭ – C♯ – G♭
1 – 3 – b7 – b9 – #9 – b13
The altered dominant draws on the altered scale, whose tensions include b9, #9, #11, and b13 over a dominant. This representative formula is 1, 3, b7, b9, #9, b13; pianists often omit the root when a bassist supplies it.
The Bb7alt chord sounds distinctive, with a altered dominant character. Its notes are Bb, D, Ab, Cb, C#, Gb. This chord is commonly heard in jazz.