As their name suggests, common note chord progressions are progressions of non-related chords which are united by a common note, or common notes.
The technique can be used for part of a song, such as in the introduction to the Red Hot Chili Pepper’s song, Under the Bridge, or, it may form the basis of an entire song, such as Herbie Hancock’s tune, Cantaloupe Island.
In Under the Bridge, the introduction consists of two seemingly unrelated chords, D major and F sharp major which are connected by the common note F sharp.
In Cantaloupe Island the progression consists of the chords, F minor – D flat seventh – D minor – F minor. Because the progression is framed by F minor chords, it may seem that this is the key of the tune. However, if we consider these chords in relation to the key of F minor,
we see that the F minor triad is certainly present, but the D flat seventh and D minor triads are not diatonic; the diatonic D flat chord with added seventh produces a D flat major seventh chord, not dominant seventh, while the diatonic triad on D is diminished, not minor.
Looking again at Cantaloupe Island’s chord progression, we see that there is two common notes between the F minor and D flat seventh chords (F and A flat), and one between the D flat seventh and D minor (F) chords.
The common note uniting all three chords (F) is also the root of the chord which frames the other two: F minor. In this way, cohesion is achieved on a couple of levels: through the use of the common note, and also, through the use of the F minor triad to begin and complete the progression. These elements create an ‘F minor’ soundworld while not restricting the work solely to the harmonies of this key.