This module takes two incoming signals (audio or CV) and mixes them at a 50/50 ratio. A positive signal at the CV input will make the “up” input louder and the “dwn” input quieter. A negative signal at the CV input will have the opposite effect. A +/-2.5V CV signal (standard LFO range) will fade between 0/100 and 100/0.
At it’s heart, this module is two separate linear response VCAs controlled inversely by a single CV input. In the absence of a second input signal, the module serves as a simple VCA.