Deep Purple in A#

Deep Purple 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 A# to B (ascending half step), B to C (ascending half step), C to F (ascending perfect fourth), F to D (descending minor third), D to G (ascending perfect fourth), G to C (ascending perfect fourth), C to D# (ascending minor third), D# to D (descending half step), D to C# (descending half step), C# to F (ascending major third), F to F (ascending unison), F to G (ascending whole step), G to C (ascending perfect fourth), C to C (ascending unison), C to A# (descending whole step), A# to G (descending minor third), G to F (descending whole step). A half-step bass movement creates a strong leading-tone pull that demands resolution. The predominantly stepwise bass motion creates smooth, connected voice leading. When the progression loops, the bass returns from F to A# 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.