The four main seventh chords
Build and name major 7th, dominant 7th, minor 7th and half-diminished chords.
A triad has three notes. Put one more third on top and you get a seventh chord, the everyday harmony of jazz, soul, funk and much pop.
Triad plus a 7th
A seventh chord is a triad plus the 7th above the root, a third stacked on the 5th. It has four notes, 1 3 5 7, and the qualities vary. These are the four main types, from C:
| Chord | Formula | Notes | Stacked thirds | Site symbol (EN / IT) | Other forms |
|---|---|---|---|---|---|
| major 7th | 1 3 5 7 | C E G B | M3 m3 M3 | Cmaj7 / Do maj7 | CM7, CΔ7, CΔ, Do 7+ |
| dominant 7th | 1 3 5 ♭7 | C E G B♭ | M3 m3 m3 | C7 / Do 7 | — |
| minor 7th | 1 ♭3 5 ♭7 | C E♭ G B♭ | m3 M3 m3 | Cm7 / Do m7 | Cmin7, C−7 |
| half-diminished | 1 ♭3 ♭5 ♭7 | C E♭ G♭ B♭ | m3 m3 M3 | Cø7 / Do ø7 | Cm7♭5 |
Reading the symbols
- In Cmaj7, “maj” describes the 7th: a major triad with a major 7th.
- In Cm7, “m” describes the triad: a minor triad with a ♭7.
- A plain 7 (C7) always means a ♭7 on a major triad: the dominant seventh.
The interval between the root and the 7th is a major 7th (11 semitones, one fret below the octave) or a minor 7th (10 semitones, two frets below the octave). On the bass, the ♭7 is two strings up at the same fret as the root (lesson 4.3).
Seventh chords sound richer and less “final” than triads. The dominant 7th in particular wants to move (lesson 10.4). The Chords for Bass tool shows all four types on every root.
Play 1–3–5–7 arpeggios of Cmaj7, C7, Cm7 and Cø7 one after the other. Then do the same from G (fret 3 on the E string).