Diatonic seventh chords
Build the seven seventh chords of a major key and of a minor key.
In lesson 8.1 you stacked three scale notes on each degree. Stack four, and every key gets a family of seventh chords.
In a major key
Stacking four scale notes on each degree of the major scale gives these chords. The pattern is the same in every major key: Imaj7 ii7 iii7 IVmaj7 V7 vi7 viiø7. The quality suffix follows the numeral.
| Key | Imaj7 | ii7 | iii7 | IVmaj7 | V7 | vi7 | viiø7 |
|---|---|---|---|---|---|---|---|
| C | Cmaj7 | Dm7 | Em7 | Fmaj7 | G7 | Am7 | Bø7 |
| F | Fmaj7 | Gm7 | Am7 | B♭maj7 | C7 | Dm7 | Eø7 |
| G | Gmaj7 | Am7 | Bm7 | Cmaj7 | D7 | Em7 | F♯ø7 |
| B♭ | B♭maj7 | Cm7 | Dm7 | E♭maj7 | F7 | Gm7 | Aø7 |
There is only one dominant 7th in a major key, on V. A 7-chord on another degree is a strong sign of a chord from outside the key (Module 14), or of the blues (Module 12).
In a minor key
From the natural minor scale the chords are i7 iiø7 IIImaj7 iv7 v7 VImaj7 VII7.
| Key | i7 | iiø7 | IIImaj7 | iv7 | v7 | VImaj7 | VII7 |
|---|---|---|---|---|---|---|---|
| Am | Am7 | Bø7 | Cmaj7 | Dm7 | Em7 | Fmaj7 | G7 |
With the harmonic minor’s raised 7th, the important changes are V7 (E7 in Am), the usual dominant in minor, and vii°7 (G♯°7). The i(maj7) and III+maj7 chords are also possible but less used.
In C, play the arpeggio of each diatonic seventh chord in order (Cmaj7 to Bø7), saying its type.