Watch the name
The term “sixth chord” has two meanings:
- in classical theory it is the first inversion of a triad (figure 6: C/E);
- in jazz and pop theory it is a triad with an added major 6th (C6). This card covers the second meaning.
The qualities
| Symbol | Notes on C | Structure | Color |
|---|---|---|---|
| C6 | C E G A | major triad + major 6th | sweet, retro, swing |
| Cm6 | C Eb G A | minor triad + major 6th | Dorian, melancholic-elegant |
| C6/9 | C E G A D | major + 6th + 9th | open, pentatonic, jazz ending |
| Cm6/9 | C Eb G A D | minor + 6th + 9th | bossa, cool jazz |
| Cm(b6) | C Eb G Ab | minor + minor 6th | rare as a symbol; often written Abmaj7/C |
In Cm6 the sixth is major (A natural): it is the characteristic note of the Dorian mode and of melodic minor.
Ambiguity and function
- C6 = Am7/C: same notes (C E G A). The bass and the context decide: if the bass is C and the chord is the tonic, it is C6.
- Cm6 = Aø7/C: same notes (C Eb G A). In jazz Cm6 is a minor tonic; Aø7 is a ii of the minor. This equivalence allows the same shape to be used for two functions.
- Rameau's added sixth (sixte ajoutée): F–A–C–D on the IV degree; it can be read as IV with an added 6th or as ii6/5 (Dm7/F). Rameau made it a model case of “double emploi”.
Why jazz uses the 6 on the tonic
In traditional jazz and swing the music often ends on C6 or C6/9 instead of Cmaj7: the 6th does not create the minor 9th that the major 7th produces against a root in the melody, and it is more “neutral”. Barry Harris built a whole method on the “6th diminished” scale: the scale C D E F G G# A B alternates C6 (C E G A) and B°7 (B D F G#), creating harmonic movement over a single tonic.
Practical voicings
- Piano: C6/9 with the left hand playing C–G and the right hand E–A–D (stacked fourths: E–A–D), a typically “modern” shape.
- Guitar: the C6/9 shape with the root on the 5th string (x3223x) is one of the most commonly used ending voicings in funk and jazz.
- Pad: C6 played as E–G–A–C (an inversion with the 6th and the root close together) produces an internal major second that adds brightness.
Examples in real songs
- “She Loves You” (The Beatles, 1963): the song ends on a G6 chord, famous because it sounded “jazzy” in a beat context.
- “Summertime” (Gershwin): often harmonized with Am6 as the tonic, the Dorian color of the major 6th.
- “My Funny Valentine” (Rodgers and Hart): the chromatic line Cm – Cm(maj7) – Cm7 – Cm6 reaches the sixth as the fourth step of the “line cliché”.
- In big band endings (Count Basie) the 6/9 chord is the most typical closing voicing.
Use in production
- In lo-fi and neo-soul the m6 and the 6/9 give a “vintage” color without the density of a 13.
- In 1980s synth pop a 6 chord on the tonic, in a pad with chorus, makes the chorus airier than a triad.
- Watch the bass: in a Cm6 play the root C; if the bass plays A, the ear hears Aø7 and the function changes.
Exercise
- Play C – C6 – Cmaj7 – C6 as a vamp and listen to the movement of the inner voice (G – A – B – A).
- Build Cm6, Fm6, Gm6, Dm6 and use them as tonics in a 4-bar Dorian loop.
- Replace the final chord of one of your songs with a 6/9 and compare it with the plain triad and with the maj7.
Related topics
Seventh chords: catalog; Ninth chords; Dorian mode; Melodic minor; Chord inversions and six-four chords.