The Story
You know the sound. It’s the "happy accident" of the late 70s: a circuit that generated distortion not just by using clipping diodes, but by pushing an op-amp so hard it physically couldn't slew fast enough to keep up. That specific, primitive failure mode is what gives this circuit its legendary "yeowl." It’s dirty, it’s aggressive, and it’s perfect.
So why build another one?
Because as good as the original is, it has limits. The Sexy Rodent is our attempt to take that classic topology and uncage it. We kept the core "slewing" gain stage that defines the sound, but ripped out the restrictions.
The stock circuit is notorious for strangling your low end. We fixed that with the Sweep control (a fully variable implementation of the classic "Ruetz" mod). This lets you alter the frequency response of the gain stage directly, moving from the tight, mid-focused bite of the 80s to a massive, blown-out fuzz tone that shakes the floor.
We also wanted texture options without the hassle. The Clip switch lets you toggle between the classic Silicon crunch, the compressed, spongy feel of Germanium, or the loud, open roar of LEDs.
The Open-Source Philosophy
Like everything at YGN, the Sexy Rodent is built on our Open Source Framework. This pedal is actually the "Reference Build" of the Framework, assembled by us to show exactly what the platform is capable of. We make these because we love the sound, but we also build them to show you what you can achieve. Whether you buy this pedal or download the files to make your own, the goal is the same: make it loud, and make it yours.
Controls
Front Panel
Volume
Adjusts the output volume of the effect.
Gain
Sets the amount of distortion. The range of this control is pretty wide, it covers ground from mild overdrive to straight-up fuzz. This is also dependent on the selected clipping option.
Tone
Adjusts the cut-off frequency. Turning this knob clockwise will filter more higher frequencies out.
Sweep
Adjusts the frequency response of the op-amp gain stage. Turning this knob clockwise will allow more low end to be clipped. Fully counter-clockwise is equivalent to the stock value.
Clip
Selects the clipping mode between LED, silicon and germanium diodes. Each will have their own threshold and will give a different character to the distortion.
Internal Controls
Effect Board
Mellow
Setting this on will tame the beast a little. It will filter some higher frequencies out at the clipping stage resulting in a slightly less aggressive, smoother sound.
IO Board
Mode
This jumper allows you to set the power-on state of the pedal. With the jumper present it will stay off and without the jumper it will switch on upon powering.
Bright
This trimpot allows you to set the brightness of the status LED.
Tips & Tricks
Clipping vs. Headroom
- Germanium diodes have the lowest ceiling. They compress early, giving you rich saturation and a lower output volume. It typically won't push your amp very hard.
- LEDs on the other hand have a very high ceiling. They allow for huge signal swings before clipping. Use this mode if you want to use the pedal as a dirty boost to drive your tube amp's preamp into natural saturation.
- Silicon diodes sit in the middle ground, though still on the lower side of the headroom ceiling. This is the diode flavor found in most stock RATs.
Dialing in the "Sweep"
Stacking Strategy
- Tighten the lows: Put a mid-hump drive (like a Tube Screamer or Klon-style circuit) before the Rodent. This cuts the bass before it hits the distortion stage, keeping things tight even with the Gain cranked.
- The Doom Stack: Run the Rodent into a mid-scooped fuzz (like a Big Muff). Use the Rodent's mid-focus to punch through the mix, adding a gnarly texture to the smooth wall of fuzz.