What key is Opus One in?

B major mixes barre and open elements. The B chord itself is a barre at fret 2, but E and A are comfortable open chords forming the IV and V. The open B string rings as the root, allowing creative drone-based arrangements. B is a intermediate-level key on guitar because the open B string rings as the root and the open E strings provide the 4th — useful for sus4 voicings and drone effects. This key mixes open and barre shapes, making it a good intermediate challenge that builds fretboard fluency.

Voice Leading

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

Scales for Improvisation

B 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, B Mixolydian adds the flat seventh for an authentic blues-rock edge.

swing2/2 · 29 bars · Form: AABA

Chords: Si, Mi9, Do♯9, Do♯m7, Fa♯9, Sol9, Re, Sim7, Mim7, La7♭9, Re6, Si7♯5, La9♯5, Fa, Rem7, Solm7, Do7♭9, Fa6, Fa♯13.

Scales for Improvisation Si bebop, Si bebop major.