The Fredric Effects Mutant Fuzz is based on the rare Brazilian Regulus VIII fuzz associated with Os Mutantes.

Circuit-wise, the Regulus VIII shares some similarities with a silicon Fuzz Face, but has a noticeably more gritty, cutting and treble-forward character. Fredric’s version stays close to the original circuit while adding practical improvements for modern use, including improved power filtering and RF interference suppression.

The gain is intentionally fixed at a sweet spot, though the pedal responds well to the guitar’s volume control and can clean up considerably when rolled back.

This updated version expands on the original design with:

• Continuously variable tone control in place of the original tone switch
• External bias control
• Wider bias range for everything from gated, sputtery fuzz to smoother sustained tones
• Improved power filtering
• RF interference filtering
• Professionally screen-printed artwork by Stacey Hine
• Powder-coated enclosure

It is a particularly cool fuzz for anyone interested in the more unusual side of late-1960s psychedelic guitar sounds — raw, aggressive and very different from the typical Fuzz Face or Tone Bender.