Packing a classic fuzz pedal in with an all-pass filter circuit, the Malekko Plus Ultra 213 can give you the most intense fuzz you could imagine or dial it back for something more chilled out and mellow. Stomping on the Filter switch gives you a completely new dimension of harmonic breakdown, allowing you to sweep through frequencies to find the right position for you. Plug in an expression pedal for some vintage wah tones, or use the all-pass filter to tweak frequency peaks as much or little as you want.