A minor sixth is the chord
you get when you take a minor triad
and add the sixth note of the scale
. They're notated Cm6
For example, an F minor triad is F Ab C. The sixth note of the F scale (major or minor) is D, so the Fm6 chord consists of F Ab C D.
Compare with the major sixth: the only difference is the underlying triad.
This chord is functionally similar to the minor seventh, flat 5
) built on the relative minor
: the component notes are identical, but the root note
is of course different:
Gm6 = G Bb D E
Em7b5 = E G Bb D
The two can be interchanged with little bother for the sake of an effective bassline.