"Mike Maghakian" wrote in message
om...
HI, BA,

check this: http://www.geocities.com/toddemslie/...electivity.htm


I have to disagree with him. Yes, various subcarriers are found above 50
KHz, but, as in television, the main modulation goes much higher than
that... i.e. the L+R modulation runs to 75 KHz deviation, and restricting
the bandpass below that introduces distortion. The way I was taught is:

Volume= how FAR the carrier is deviated
Pitch (tone)= how FAST the carrier is deviated.

It's more complicated than that, but it's a rule of thumb.