Old Devil Moon in A

Old Devil Moon in A

Key of A

A major is a rock and blues cornerstone. The open A string delivers a strong root, while both E strings ring as the fifth. Classic A-D-E progressions practically play themselves with open cowboy chords. The open high E is the fifth, reinforcing power. A is a beginner-level key on guitar because the open A string is the root and the open E strings provide the fifth above and below, creating a massive low-end anchor. Beginners will find this key approachable since most chords use open voicings with minimal stretching.

Voice Leading

The bass line moves through A to E (descending perfect fourth), E to A (ascending perfect fourth), A to D (ascending perfect fourth), D to D (ascending unison), D to D (ascending unison), D to G (ascending perfect fourth), G to C (ascending perfect fourth), C to F (ascending perfect fourth), F to A# (ascending perfect fourth), A# to E (ascending tritone), E to A (ascending perfect fourth), A to F# (descending minor third), F# to F# (ascending unison), F# to F# (ascending unison), F# to F# (ascending unison), F# to B (ascending perfect fourth), B to B (ascending unison), B to E (ascending perfect fourth), E to A# (ascending tritone), A# to E (ascending tritone), E to D (descending whole step), D to C# (descending half step), C# to C (descending half step), C to B (descending half step), B to A# (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 A# to A by half step.

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.