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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?

Direct Prices

Harmonic Percolator: £95
Utility Perkolator: £95
Unpleasant Companion: £95
Grumbly Wolf: £95
Scrambled Brainz: £90
Demon Fuzz: £80
Dresden Synth Fuzz: £90
Green Muff: £90
I Got Me A Pocket Weasel: £90
Do The Weasel Stomp! £140
Super Unpleasant Companion £140
Kl*n Buffer £35
Foxrite £95
Zombie Klone £120
Golden Eagle £120
King of Klone £225
West Germany Tremolo £90
Mutant Fuzz £80


We post anywhere in the world, typically £10 to the USA and Europe for one pedal, a little more for two. Within the UK we use first class signed-for, which costs £5 but is tracked, insured and arrives the next working day.

Fredric Effects accept Paypal, but if you're in the UK you can save £5 on each pedal by paying by bank transfer instead.

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