 Taking a major cue from the first generation of Mesa Boogie amplifiers such as the Mark I (itself a modified Fender design), the Prosonic used additional gain stages in the preamp section that cascaded into one another.Although Fender had been designing amps with some facility for built-in distortion/overdrive since at least the late 1960s, never before had they arrived at a sound so readily usable for modern high-gain styles of music, and far removed from what many players consider to be archetypical Fender tones.The Prosonic's factory manual states, "Gain 1 functions as a standard gain stage whereas Gain 2 functions similar to a compressor, adding sustain while reducing 'edge' when the volume is increased.