John Frusciante’s Micro-Tron IV Mu-Tron Envelope Filter

This pedal was seen on John’s pedalboard at a gig that the Red Hot Chili Peppers played at the Apollo Theater on September 13, 2022 (for images see John Frusciante’s Unlimited Love/Dream Canteen Pedalboard). This is the only time the pedal was seen on his pedalboard, so it’s unknown precisely for what purpose he was using it.

For whatever reason, John removed the foot switch labeled “Up and Down” from the pedal. This switch basically allows you to switch between an auto-wah and a down-swoop sound.


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