The term ‘chromatic mediants’ probably isn’t something you’ll have come across very often in your songwriting pursuits, but working these mysterious creatures into progressions can be a useful way to expand your palette of chords beyond the realms of your regular, day-to-day diatonic triads.
So what is a chromatic mediant anyway? In music theory, diatonic means ‘in the key’, while chromatic means ‘not in the key’. So if you have the scale of C major, which contains the notes C, D, E, F, G, A and B, those notes are all diatonic to the key of C major. Something like a G# note, however, is not in the key of C major, so in this context G# is described as chromatic. The same thing goes for chords – when in…