Moonglow in A#

Will Hudson / Irving Mills / Eddie DeLange(1933)swing

Moonglow in A#

Key of A#

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 C to D# (ascending minor third), D# to A# (descending perfect fourth), A# to C (ascending whole step), C to F (ascending perfect fourth), F to A# (ascending perfect fourth), A# to F# (descending major third), F# to D# (descending minor third), D# to A# (descending perfect fourth), A# to A (descending half step), A to G# (descending half step), G# to G (descending half step). 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 C by perfect fourth.

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.

swing4/4 · 24 bars · Form: AB

Chords: Cm7, D♯m, A♯6, C7, F7, A♯, F♯7, D♯m7, A♯7, A7, G♯7, G7.

Scales for Improvisation A# bebop, A# bebop major.

Diatonic chords: See all chords in the key of A#