How do I make a tone of 440 Hz with a modulation of 5.5Hz and a deviation of 1/13 of the base?
I think your’e missing a value. You want it to switch between values like Frequency Shift Keying, or sine modulation like a broadcast transmitter? I don’t think we can do either one, but it’s good to know.
Try this code in the Nyquist Prompt effect (http://manual.audacityteam.org/o/man/nyquist_prompt.html):
(setf fc 440.0) (setf depth (/ 1.0 13.0)) (setf modHz 5.5) (let ((mod (mult depth fc (lfo modHz)))) (fmosc (hz-to-step fc) mod))