Sound Design Stack Exchange is a question and answer site for sound engineers, producers, editors, and enthusiasts. It only takes a minute to sign up.
Sign up to join this community
How would I calculate the amplitudes, phases, and frequencies of the harmonic peaks resulting from frequency modulating (and/or phase modulating) a waveform stored in frequency domain representation?
(In my case it is enough to only be able to deal with integer multiples of the waveform's fundamental frequency)
Not entirely sure what you mean with the following phrase?
a waveform stored in frequency domain representation?
However, with FM the frequencies of the partials can be easily calculated as a function of the carriers frequency and the modulators frequency, such that C, C+M, C+2M, C+3M, etc. and C-M, C-2M, C-3M, etc. give the partials.
Calculating the amplitudes of the partials is more complicated and requires a Bessel function based on the modulation index. Probably not calculations you want to do by hand.
By using a good spectrum analyzer and reading the values before and after is probably the easiest. I have no suggestions for an analyzer, but there are lots, so you might find something that's suitable, if you do a bit of searching.
I don't know if an automatic solution exists, but it would be a simple program (and can be done in e.g. Matlab and such as well).
Depending on what kind of frequency modulation, there ought to be mathematics as well for finding the information. Although the solution would need to be computed.
