Seventh-Chord Shapes: Play Them All Over the Neck by Root String

Stack a seventh on top of a triad (1-3-5) and you get a seventh chord. The four most common: major 7th maj7 (1-3-5-7, bright and laid-back, like Cmaj7); dominant 7th, written 7 (1-3-5-♭7, it wants to pull to the tonic, like G7); minor 7th m7 (1-♭3-5-♭7, mellow, like Am7); half-diminished m7♭5 (1-♭3-♭5-♭7, tense, often used on the ii of a minor key). Memorize the “flavor” of each first.

Same idea as CAGED: seventh chords also have a few fixed shapes for “root on the 6th string,” “root on the 5th string,” and “root on the 4th string.” Once you've memorized a seventh chord's hand shape with the root on the 6th or 5th string, you can shift it along that string to any key — wherever the root lands is the key of that seventh chord.

To start, learn one of each: dominant 7 with the root on the 6th string, and major 7 and minor 7 with the root on the 5th string. Those three are enough to use, swapping among them, across most of a song.

Swap the triads in your accompaniment for the matching seventh chords (C→Cmaj7, Am→Am7, G→G7) and the color instantly gets richer. Jazz, bossa nova, R&B, and neo-soul are basically all built on seventh-chord voicings — this is the step that actually puts to use what you learned back in Stage 6's “intro to seventh chords.”