Now here's where we get musical.
Overtones.
Here's the dealio.
When two pitches are played at the same time, the sound waves combine.
The highs and lows in the air pressure combine and produce a different sound wave altogether.
When this is perfectly periodic, it's called an overtone, because the tones are overlapping!
It's very sensible.
The lowest frequency is the one at which the entire wave vibrates.
The overtones vibrate at integer multiples of the base frequency, or the fundamental frequency.
Exact integer multiples of the fundamental frequency are called harmonics.
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What this means to anyone who didn't major in physics in college, is that these waves shake a lot and it sounds good!
WHOO!
©2006 anthony, christina, and teresa