Function f(x) Accufunkture Envelope-Controlled Filter $155.00 Quantity Function f(x) Accufunkture Envelope-Controlled Filter quantity Add to cart Description Function f(x) Accufunkture Envelope-Controlled Filter Additional information Model Envelope Filter Add to Wishlist Category: Effects/Pedals/Synths - Used. Related Products Pigtronix Philosopher’s Tone $115.00 Ibanez Multi-Effects UE300 $299.00 Fender Blender Fuzz (1968) $525.00