FM with non-sinusoids #474
Description
(Forked from #470).
The analog FM available in the Prophet 5 rev4 sounds amazing. It appears to come from using a sawtooth modulator to modulate a sawtooth carrier. I don't think this is possible with the current AMY interface, but in principle the FM LUT routines could handle it. Except, they implement phase modulation instead of direct frequency modulation, so some additional modification will be needed.