FollowTroller is an unusual amplitude and filter effect.
FollowTroller allows you to control the enveloppe of sound (VCA) or his cut off frequency (and his resonance) with an other audio signal. It's pretty similar to the using of an enveloppe follower that convert the audio signal into a cv signal.
How to use Followtroller: Open a new stereo group or FX track into your DAW. Set panaromic of the sound that will generate an enveloppe to the extrem left and send it the group or FX track. Set panoramic of the sound that will be modulate to the extrem right and send it to the group or FX track. You can invert the connnection (by pushing the invert button) if you invert your pan, or to test sound experimentations.