Music,
has a lot in common with Electrical theory.
It is a very physical thing.
Take for instance, a guitar string, it has a fundamental frequency (compare that to 60Hz)
A guitar also has harmonics along it's fret-board (any guitarist will tell you that).
Eddie Van Halen almost built a career on this fact (tapping).
I've used a bass before in one of my Ham Radio classes to explain Harmonics, as in 2x, 3x and 4x the fundamental.
