A#11

Extended · A# root / B♭

A#11 / B♭11

Dense and atmospheric. The 11th adds a suspended quality over the dominant.

0 st4 st7 st10 st14 st17 st

Notes in A#11

BbRoot
D3rd
F5th
Ab7th
C9th
Eb11th

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#11, A#m, A#7, or another quality — the hardest and most useful ear training skill.

11th in All 12 Keys

Other Chords in A#

Related Extended

About the A#11 Chord

The A#11 chord is a 11th chord built on A# (also written B♭11). It contains the notes Bb, D, F, Ab, C, Eb — the root, third, fifth, seventh, and extensions.

Dense and atmospheric. The 11th adds a suspended quality over the dominant. Practising the A#11 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.