Ligma Electronics – Critical Mass
Dual Drive Pedal | Glow-in-the-Dark Finish | Assembled in Canada
Critical Mass is a compact dual-drive pedal that combines two legendary circuits - the SD-1 and the RAT - into one explosive, flexible unit. Inspired by the “Demon Core” incident, it’s designed for players who want a wide palette of overdrive and distortion tones in a small enclosure.
SD-1 Side - A mid-forward, low-gain overdrive with smooth clipping - ideal for everything from bluesy grit to stacked high gain. We've added a clipping mode switch that lets you toggle between classic SD-1 asymmetrical diodes and symmetrical silicon for a more Tube Screamer-like response. Powered by a NE5532 op-amp, this side delivers low noise, high headroom, and clean articulation.
RAT Side - A faithful recreation of the original circuit’s snarling distortion, featuring a filter voicing switch to open up the low end for fatter riffs and heavier tones, specifically tuned for 5 string bass. Built around the OP07 op-amp, it offers greater precision and thermal stability than the original LM308, preserving the signature sound while improving consistency.
Inside the enclosure, an internal red switch activates the “Clean RAT” mod - removing the clipping diodes to transform the RAT into a powerful, uncompressed overdrive or clean boost. This mode is perfect for cutting through the mix or driving your amp harder without added distortion.
Additional Features
- Internally adjustable bias control and LED brightness trimmer for dialing in feel and aesthetic.
- A dedicated voltage regulator ensures a stable bias point, improving reliability across power supplies.
- Compact footprint, designed to sound great with clean or dirty amps, solid-state or tube.
- Glow-in-the-dark finish with UV LEDs that charge the surrounding paint for a faint glow after each circuit is disengaged.
- Designed, assembled, and tested in Alberta, Canada.
U.S. buyers: U.S. orders are temporarily suspended due to the current 50% tariff affecting Canadian-made effects pedals. Join the mailing list at and I’ll let you know when regular U.S. shipping resumes.
If you live in the U.S. and are seriously interested in buying a pedal in the short term, email . We can probably figure something out.
Other international buyers: Email with your country and postal code for a shipping quote before ordering.
Questions?
Note that the "Glow-in-the-Dark" edition is sonically identical to the "Bright Blue Flash" edition.
| Condition | Brand New (New) Brand New items are sold by an authorized dealer or original builder and include all original packaging.Learn more |
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