If you’ve come up with a melody you like, it’s easy to think that the creative process is now over – it’s just a question of finding the obvious ‘right’ chords to go underneath. But a melody only takes you half the way there, because harmony changes everything.
An example. Take this simple 8-bar melody …
Chances are that, when you heard that melody, your brain assumed a typical harmonic structure. If that wasn’t the case, try listening again and get a feel for what might go alongside the melody.
Now here’s that same melody with another guitar playing a harmony (essentially a routine third above the melody), plus an electric piano and bass which together establish the chord progression: G D Em C C D G D. Is that what you had in your head? It’s all fairly obvious.
But what if we shifted the harmonic structure while keeping the same melody? We’d end up with something very different …
The chord structure is very different: G Fmaj7 Em7 Ebmaj7 C9 D+ G D+ and that gives the piece a quite different feel. Interestingly, the harmony guitar part only had to be modified very slightly to match the chords beneath.
The creative possibilities for the composer are almost endless. You can take almost any song and transform it by the harmonies you use. Of course, that’s what jazz musicians have been doing for decades.