What key is Opus One in?

G major is the singer-songwriter's key. The open G, B, and D strings spell out the full G major triad with zero fretting. Add the open high E for a Gadd6 shimmer. Nearly every diatonic chord (Em, Am, C, D) has a comfortable open voicing. G is a beginner-level key on guitar because the open G, B, and D strings form a complete G major triad without fretting a single note, and the open low E adds a rich 6th color. Beginners will find this key approachable since most chords use open voicings with minimal stretching.

Voice Leading

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

Scales for Improvisation

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

swing2/2 · 29 bars · Form: AABA

Chords: Sol, Do9, La9, Lam7, Re9, Re♯9, La♯, Solm7, Dom7, Fa7♭9, La♯6, Sol7♯5, Fa9♯5, Do♯, La♯m7, Re♯m7, Sol♯7♭9, Do♯6, Re13.

Scales for Improvisation Sol bebop, Sol bebop major.