6th chords: the sweet major sixth

A 6th chord is a major chord with one extra note that makes it sound finished and a little bit elegant. It is the last chord of a swing tune, the warm chord at the end of a ballad, the major chord that refuses to sound plain. It is also the chord family with the best trick in all of guitar harmony: every 6th chord has exactly the same notes as a minor seventh chord. Understand that, and a whole set of voicings you already know acquires a second name.

What a 6th chord is

Take a major triad and add the major sixth above the root. The formula is 1, 3, 5, 6.

The sixth is the note that carries the color, so it is the one note you can never leave out. A 6th chord with no sixth is just a major chord.

The key idea: C6 and Am7 are the same notes

C6 is C, E, G, A. An A minor seventh is A, C, E, G. Same four notes. What decides which chord you hear is the bass and the job the chord is doing.

• You hear C6 when C is in the bass, the song is in C major and the chord is a point of rest, typically at the end of a phrase: F, G7, C6.
• You hear Am7 when A is in the bass and the chord is heading somewhere, as the ii of G major: Am7, D7, G.

The rule is general: every 6th chord shares its notes with the minor seventh chord a minor third below. D6 is Bm7, E6 is C#m7, F6 is Dm7, G6 is Em7, A6 is F#m7, B6 is G#m7. The practical consequence is that your minor seventh shapes become 6th chords the moment you put the other root in the bass. The minor seventh chords page has those shapes.

6 versus maj7, 7 and 13

Four chords all start from C major and add one note above. The note you add decides everything.

The C13 row is the one that confuses people. The 13th of C and the 6th of C are both A. But a 13 chord contains a minor seventh, so it is a dominant chord, while a 6 chord has no seventh and stays at rest. If the chart says C13, you need the Bb; if it says C6, you must not play it.

In a final chord, a 6 is often the safer choice than a maj7. The major seventh sits a half step under the root and can rub against a melody that lands on the tonic; the sixth sits comfortably under it. The major seventh chords page shows the other side of that choice.

The shapes to learn

The open 6th chords are all a single finger away from an open major chord you already know, which makes them the easiest richer chords on the guitar. G6 lifts the high G off a G major. A6 lays the first finger across four strings. D6 lets the second string ring open. E6 adds the fourth finger to an E major.

The open C6, x 3 2 2 1 0, gives C, E, A, C, E. There is no G in it, so strictly speaking it is a C6 with no fifth. That does not matter in practice: the A carries the color, and the shape sits one finger away from the C major you already play.

The last diagram is the one to keep for later. Root on the sixth string, fifth string muted, four notes in a narrow span, nothing doubled: it is the 6th chord voicing of swing and jazz rhythm guitar, and because it has no open strings it moves anywhere.

Two more open shapes complete the set. F6 is 1 x 0 2 1 1, with the thumb or the first finger on the low F; without that bass note the same shape is a Dm7. B6 is x 2 1 1 0 2, a complete B6 with no barre. And G6/B puts the third of G6 in the bass, which makes it a smooth step between C and Am.

How to use 6th chords

The 6th chord is above all a resolution. It ends a phrase with more warmth than a plain major chord and less suspense than a maj7. Play these three endings back to back and listen to the last chord change color:

The same works at the end of a ii-V-I: Am7, D7, G6 (x02010, xx0212, 320000) or Bm7, E7, A6 (x24232, 020100, x02222). The chord progressions page has more of these to drop a 6th chord into.

To practice, swap each open major chord for its 6th and back again: G to G6, A to A6, D to D6, E to E6, C to C6. One finger moves each time, and the point of the exercise is to hear the sixth arrive and leave. If any of the major shapes is still unsteady, the major chords page comes first.