Ain't Misbehavin' in La#

Ain't Misbehavin' in La#

Fats Waller's stride piano classic is a masterclass in Mixolydian and Blues language layered over a swinging A# groove. Bebop Major lines sit naturally on top of the changes, bridging the stride tradition with modern improvisation. The A#Maj7 – Gm7 – Cm7 – F7 – A#7 – D#6 – Edim7 – G#7 – Dm7b5 – G7b9 harmony is a perfect vehicle for developing blues phrasing and rhythmic authority.

Ain't Misbehavin' in La#

A# (Bb) major requires barre chords rooted at fret 1 on the A string or fret 6 on the E string. Despite the barre demands, it is a common key in funk, New Orleans R&B, and brass band music. The open D string can ring as the major third for added color. A# is a intermediate-level key on guitar because the open D string is the major 3rd of Bb, adding a bright color if allowed to ring. Expect to rely on barre chords throughout, which builds hand strength and unlocks the entire fretboard.

Voice Leading

The bass line moves through A# to G (descending minor third), G to C (ascending perfect fourth), C to F (ascending perfect fourth), F to A# (ascending perfect fourth), A# to D# (ascending perfect fourth), D# to E (ascending half step), E to G# (ascending major third), G# to D (ascending tritone), D to G (ascending perfect fourth). A half-step bass movement creates a strong leading-tone pull that demands resolution. The root motion by larger intervals (fourths and fifths) gives each chord change a strong, decisive character. When the progression loops, the bass returns from G to A# by minor third.

Scales for Improvisation

A# major pentatonic works because every note is either a chord tone or a safe passing tone — there are no avoid notes. For soloing, this means you can play freely without clashing. Over dominant seventh chords, A# Mixolydian adds the flat seventh for an authentic blues-rock edge.