A# 6/9 (A#6/9)
Also written as Bb 6/9 (Bb and A# are the same key).
Notes in A# 6/9
Inversions
Same notes as A# 6/9, with a different chord tone as the lowest note. Useful for smoother movement between chords instead of jumping around the keyboard.
Root position
A# in the bass
1st inversion
D in the bass
2nd inversion
E# in the bass
3rd inversion
G in the bass
4th inversion
B# in the bass
Open voicings
A close-position chord like A# 6/9 can sound cluttered in the middle of the keyboard. Jazz players open it up by dropping one note down an octave, spreading the same notes wider without changing the chord.
Drop 2
G on the bottom
Drop 3
E# on the bottom
Press A#, D, E#, G and B# together on the keyboard and you're playing A# 6/9.
A major triad carrying both a sixth and a ninth, with no seventh in sight. That combination is bright and full without the pull of a dominant or major seventh chord, which makes it a favorite way to close a song on a major chord that still sounds a little more interesting than a plain triad.