I stumbled upon this concept by accident, even if you don’t get a real and versatile FM it’s interesting to experiment with.
There are obvious limitations but perhaps it is just a matter of concept and technique.
Instead of using the traditional LFO as a modulator, I used an envelope with time synchronization and a very short loop of 20 milliseconds that correspond to 50 Hz.
You can modify loop size from 10 millisecond (equivalent to 100 Hz) to more than 16 seconds.
There are many improvements to be made and parameters with which to experiment, envelope shape and pitch range are the two most obvious.
FM.xrni (9.5 KB)
I hope it will be stimulating and fun
This trick was already known by @gentleclockdivider and others. I apologize for having proposed it again.