A#7

Sevenths · A# root / B♭

A#7 / B♭7

Tense and driving. Creates the strongest pull toward the tonic.

0 st4 st7 st10 st

Notes in A#7

BbRoot
D3rd
F5th
Ab7th

A# / Bb is a favourite for horn players and jazz musicians. Many blues and jazz standards are in Bb.

Identify the Chord Quality on A#

Each chord below is played on A#. Listen and identify whether you heard A#7, A#m, A#7, or another quality — the hardest and most useful ear training skill.

Dominant 7th in All 12 Keys

Other Chords in A#

Related Sevenths

About the A#7 Chord

The A#7 chord is a dominant 7th chord built on A# (also written B♭7). It contains the notes Bb, D, F, Ab — the root, third, fifth, and seventh.

Tense and driving. Creates the strongest pull toward the tonic. Practising the A#7 chord across different voicings and contexts builds the harmonic recognition that lets you identify it instantly in any musical setting — whether in a band mix, a recording, or a live performance.