Ask a synth enthusiast to explain what synthesis is and you can sometimes end up with a rather convoluted and complicated answer. I know I am guilty of saying things like frequency modulation and watching as your friends look rather bemused...
"I want you to imagine the fly is an oscillator, and this box is a filter."
Dolby starts to shake the box to represent the electrical current and then open the box to represent the opening and closing of the filter.
"The harder I shake the box, the higher the pitch!"