Sixth chords
Structure and character
A (major) sixth chord adds a major 6th to a major triad. Sixth chords do not contain a 7th.
A major 6th can be found a whole step (2 frets) above the 5th or a half step (1 fret) below the minor 7th.
You are allowed to omit the 5th when you play a 6th chord.
Sixth chords have a dark, melancholic character. They create less tension than seventh chords and therefore tend less to push towards a chord change.
Guitar chord shapes for sixth chords
Deriving C6 from the basic C major chord shape
Starting from the "classic" C major shape, raise the G by two frets (a whole step) to get the 6th A. You may drop the 5th G.
To change the C major chord into a C6 that way, drag the slider below the chord shape to the right.
Look closely: the C6 is essentially an Am chord shape with C (instead of A) in the bass.
C6 can be seen as an Am (or Am7) chord with the minor 3rd C in the bass.
Creating C6 with the parallel Am chord
Let's build more C6 shapes by fretting Am or Am7 on the upper four strings and adding a C in the bass on the low E or A string. Here are some examples:
Creating G6 with the parallel Em (or Em7) chord
If C6 can be viewed as Am/C or Am7/C, then G6 can be derived from Em or Em7.
G6 can be seen as an Em (or Em7) chord with the minor 3rd G in the bass.
In the last Em7/G6 pair you don't even have to change the shape: it depends on which note you treat as the root (or which note a bassist would play). Whether a bassist is present or not doesn't matter - it just works!
Minor 6th chord (m6)
To play an m6 chord, take a major 6th chord and lower the major 3rd to a minor 3rd.
In the shown diagram you see C6 (with major 3rd E) changing to Cm6 (with minor 3rd Eb). Drag the slider under the chord shape to the right.
Special appearances of 6ths in chords
Minor chord with minor 6th (mb6)
You may encounter mb6 chords, but they are normally written as slash chords. For example, Cmb6 is written as Ab/C.
6/9 chord
A 6/9 chord is a 6th chord with an added 9th. It is commonly used as a song's final chord. If we followed a consistent syntax where chord extensions are written in brackets, 6(9) would be appropriate; however, 6/9 is the standard spelling and has nothing to do with the so-called slash chords.
6th and 7th in one chord: 6 vs. 13
If a chord contains both a 7th and a 6th, the 6th is notated as 13 in the chord symbol (not 6), because it is an extension of a seventh chord. Whether we count 6 or 13 scale tones up from the root, we'll end up with an equally named note. The absolute pitch is irrelevant for the chord type. The difference is functional: 6 and 13 both mean a 6th, but writing 13 tells the player that there is also a 7th in the chord → e.g., G13 is a G7 with an added 6th; it can also be written G7(13).
If a chord contains a 6th and a 7th (or maj7), write "13" instead of "6" in the chord symbol.
Chord progressions with 6th chords
Calming the harmonic movement
Example 1:
Original:
The two chords Imaj7 and IVmaj7 (here in G major) are often enough to provide the basis for a whole song. "Waiting In Vain" by Bob Marley is a well-known example.
In theory you can always add a 9 to a maj7 chord. If we play G6 instead of Gmaj7 and Cmaj7(9) instead of Cmaj7, only the bass note moves. You can also use this as a variation from time to time.
Modified:
Common chord tones and a melancholy mood are the purpose to modificate the standard chord progression of this example— reminiscent of Lionel Richie's "Hello".
Example 2:
Standard chord progression in A minor:
Modified chord progression:
Creating harmonic movement
Instead of holding a single chord (e.g., 7, maj7, m7, major, minor) for two or more bars, a corresponding sixth chord is often inserted to be played alternately with the original chord.
Example 3:
Little movement:
More movement with added 6th chords:
Reducing the bass movement
Example 4:
Two-five-one progression (IIm7 V7 Imaj7) extended by a VIm7 chord (very common):
Modified progression:
The chord shapes are shown in the previous example.
The Dm6 chord can be seen as a G7(9) without the root. C6 has exactly the same tones as Am7.
Example 5:
Chord progression with bVII7 chord (here: G7 chord in A major).
Again, Dm6 replaces G7. It doesn't matter that it contains the tones of G7(9) rather than G7(13). You can normally switch between the extensions 9 and 13 in nearly every situation. So wherever a G7(13) is written, you can normally play a G7(9) instead.
Line cliché
A melody that is ascending or descending in half steps (chromatic line) is generated by changing the chord type.