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Grumbly Wolf


A grumbly distortion/ring mod.

The Fredric Effects Grumbly Wolf is a highly versatile combined distortion, fuzz, octave and ring mod effect. Capable of everything from classic crunchy overdrive to intense octave fuzz madness. This is based on an asymmetrical hard clipping distortion circuit, followed by a great sounding octave/ring mod effect (based on the classic Green Ringer), which can be turned on and off with the toggle switch. This second stage can provide extra gain for full-on splattery fuzz, or clangy ring mod type sounds with the distortion turned down.

High Quality:

  • Custom enclosure fabricated for Fredric Effects in North London
  • Professional powder coating and screen print
  • PCB construction (not perf or vero)
  • Handmade
  • Cliff jacks
  • Alpha footswitch and pots
Powered by battery or standard center-neg DC jack, clear red LED. Small, MXR-sized enclosure.


This excellent demo is by Christian at Magnetic Effects.

Buy one now - £95

Want stick-on feet?

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