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Re: two sine tones simultaneously within one critical band
Bob Masta wrote:
> I am completely at a loss to understand how you arrived
> at your last formula. It appears that you have not simply
> added the pressure waves, but multiplied them.
cos(2pi*t) * cos(100 * 2pi*t) = cos(99*2pi*t) + cos(101*2pi*t)
This can be derived using:
cos(x1)*cos(x2) = 1/2*cos(x1-x2) + 1/2*cos(x1+x2)
Another explanation can be: two frequencies (99Hz and 101Hz) can be seen
as one absent carrier (100Hz) modulated with a modulator (1Hz).
br, Piotr Majdak
Acoustic Research Institute
Austrian Academy of Sciences