as i found my preenfm lack of drifting, i added 3 new shapes for the lfos, to make it more "analog"
Brownian : lowpass filtered noise, discrete values
Wandering : interpolated noise, continuous values
Flow : lowpass filtered & interpolated noise, continuous values
audio demo :
http://sndup.net/m8vs(only changing the lfo shape, first the 5 known shapes modulate a filter, then the 3 new ones)
https://github.com/Ixox/preenfm3/pull/34