Setembro

Setembro 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 F# (ascending whole step), F# to F# (ascending unison), F# to D (descending major third), D to A (descending perfect fourth), A to B (ascending whole step), B to B (ascending unison), B to G# (descending minor third), G# to C# (ascending perfect fourth), C# to F# (ascending perfect fourth), F# to C# (descending perfect fourth), C# to D# (ascending whole step), D# to D# (ascending unison), D# to F (ascending whole step), F to A# (ascending perfect fourth), A# to D# (ascending perfect fourth), D# to A# (descending perfect fourth), A# to C (ascending whole step), C to C (ascending unison), C to D (ascending whole step), D to G (ascending perfect fourth), G to C (ascending perfect fourth), C to E (ascending major third), E to A (ascending perfect fourth), A to D (ascending perfect fourth), D to G (ascending perfect fourth), G to C (ascending perfect fourth), C to F (ascending perfect fourth), F to F (ascending unison), F to A# (ascending perfect fourth), A# to A# (ascending unison), A# to G (descending minor third), G to C (ascending perfect fourth), C to F# (ascending tritone), F# to B (ascending perfect fourth), B to E (ascending perfect fourth), E to E (ascending unison), E to A (ascending perfect fourth), A to E (descending perfect fourth), E to A (ascending perfect fourth), A to A (ascending unison). 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 unison.

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.