D Dominant Seventh chord (D7) on the guitar fretboard

The D Dominant Seventh chord (D7) is made of D (the root), F# (major third), A (perfect fifth) and C (minor seventh). The fretboard shows every one of them across the neck in standard tuning (E A D G B E), and plays them back so you can hear the chord.

The dominant seventh adds a minor seventh on top of a major triad, which leaves a restless interval pair inside it. It lives on the neck in several overlapping shapes, since its four notes repeat on every string group. Next to it sit the major seventh, with a raised top note, and the ninth, which stacks one more note above.