ProCo RAT2 Settings Guide
One of the most versatile distortion pedals ever made — the RAT circuit has appeared on records from Eric Clapton's blues to Radiohead's art-rock to Slayer's thrash metal. The RAT2 uses a LM308N op-amp chip that produces a hard-clipped distortion with a distinctly aggressive, asymmetric character. Its unique Filter control (which is INVERTED) allows it to go from bright and cutting to dark and synth-like within a single turn.
Used by: Dave Grohl, Thom Yorke, Jeff Beck
The best ProCo RAT2 settings start with: Distortion at 6/10, Filter at 4/10, Volume at 6/10. Adjust from there based on your amp, guitar, and room volume. For Grunge / Alternative: Distortion 7/10, Filter 5/10, Volume 6/10.
⚡ Start Here — Recommended Settings
| Control | Starting Position | Range |
|---|---|---|
| Distortion | 6/10 | Clean → Fuzz |
| Filter | 4/10 | Bright → Dark |
| Volume | 6/10 | Silent → Loud |
These are universal starting points. Adjust based on your amp, guitar, and room. Scroll down for genre-specific settings and artist-documented positions.
What Each Control Does
Recommended Starting Settings
Safe starting positions for any style. Adjust from here based on your amp and room.
All values on a 0–10 scale. These are starting points — fine-tune by ear.
Settings by Genre
Mid-gain RAT character with Filter slightly darkened — the slightly compressed, mid-forward distortion that defines alternative rock. Pushing Distortion to 7 gives enough saturation for power chords without losing note definition on arpeggiated parts. Filter at 5 (above centre) darkens the fizz without killing treble. This is the setting range used on countless Pixies, Smashing Pumpkins, and Dinosaur Jr records.
Low gain with bright Filter — running the RAT2 at Distortion 4 produces a touch-sensitive, amp-like crunch that responds dynamically to picking attack. Filter at 3 (counter-clockwise) keeps treble present for single-coil articulation. Volume at 7 pushes the amp slightly, letting the amp add warmth to the RAT's hard-clipped character. Jeff Beck used similar RAT settings for his lead tone on studio sessions.
Maximum gain with darkened Filter to manage fizz — the RAT2 at Distortion 9 produces a compressed, saturated fuzz-adjacent character that is more harmonically dense than conventional metal pedals. Filter at 6 removes the upper treble buzz that becomes unpleasant at high Distortion. A noise gate after the RAT2 is essential at these settings — the RAT's high gain creates significant noise floor between notes.
Medium gain with neutral Filter — the RAT2's characteristic on complex chords and sustained notes produces a natural compression and harmonic complexity that works well for post-rock swells. Running the RAT2 into a reverb-heavy clean amp produces the dense, atmospheric character associated with Explosions in the Sky and Mogwai. Filter at 4 keeps the upper-mid presence without brightness.
Near-clean with bright Filter — the RAT2 at low Distortion settings acts as an edge-of-breakup overdrive with the hard-clipped character producing a different texture from smoother overdrives. Filter at 2 (mostly counter-clockwise) keeps the sparkle that jangle-style playing requires. This is a less common but effective RAT application for players who want an alternative to Tube Screamer-style mid-push overdrive.
Artist Settings
Documented settings used by professional guitarists on this unit.
Grohl used a RAT2 in early Nirvana sessions and on early Foo Fighters recordings. The setting targets the compressed, mid-forward grunge distortion character: Distortion at 7 provides enough saturation for power chords without crossing into metal territory, Filter at 5 slightly darkens the treble buzz, Volume at 6 at unity-ish gain. The key is that Grohl ran the RAT into a clean (or slightly dirty) tube amp and let the amp add warmth to the RAT's hard clip.
Radiohead used the RAT2 extensively on The Bends and OK Computer era recordings. The darker Filter setting (6) produces the more compressed, slightly muffled distortion character that appears on tracks like Just and My Iron Lung. The RAT's asymmetric clipping interacts differently with Yorke's clean Telecaster signal than with humbucker guitars — Filter needs to be higher (darker) to manage the Telecaster's brightness at high Distortion settings.
Beck used the RAT for its touch-responsive, amp-like character at lower Distortion settings — not as a saturation effect but as a dynamic crunch pedal. At Distortion 4, the RAT2 responds dramatically to picking attack, from near-clean at light touch to mid-gain crunch on strong downstrokes. Volume at 7 provides a slight amp push. This application treats the RAT2 more like a sophisticated overdrive than a distortion pedal and is one of its most musically expressive uses.
Also in Our Rig Database
Guitarists who feature this gear in their documented rig — explore their full setup.
Tips & Common Mistakes
- The Filter control is INVERTED — turning it clockwise makes the sound DARKER, not brighter. Counter-clockwise is brighter. Never judge the RAT2 with Filter at noon (5) as it is too dark for most applications; start with Filter at 3–4.
- The default noon settings on all three controls sound bad — this is normal and well-documented. The RAT2 requires deliberate dialling; the nominal 12-o'clock position on every control is not a useful starting point.
- Running the RAT2 into a clean tube amp produces significantly better results than into a solid-state amp. The valve power stage's natural compression and harmonic softening works with the RAT's hard clip rather than against it.
- A Tube Screamer or MXR Overdrive+ in front of the RAT2 (TS first, RAT second) adds midrange focus and tightens the low end — a classic combination for hard rock lead tones.
- At high Distortion settings, a noise gate is essential. The RAT2's high gain produces significant noise floor between notes at Distortion above 7. The Boss NS-2 or ISP Decimator after the RAT2 in the chain is the professional solution.
- The RAT2's hard clipping responds differently to humbuckers versus single coils — humbuckers produce a thicker, more compressed result and need lower Filter settings; single coils are brighter and need higher Filter settings to control treble.
FAQ
ProCo RAT2 — Common Questions
Best starting settings for ProCo RAT2: Distortion at 6/10, Filter at 4/10, Volume at 6/10. Adjust from there based on your guitar, room, and playing style.
For Grunge / Alternative: Distortion 7/10, Filter 5/10, Volume 6/10. Mid-gain RAT character with Filter slightly darkened — the slightly compressed, mid-forward distortion that defines alternative rock. Pushing Distortion to 7 gives enough saturation for power chords without losing note definition on arpeggiated parts. Filter at 5 (above centre) darkens the fizz without killing treble. This is the setting range used on countless Pixies, Smashing Pumpkins, and Dinosaur Jr records.
For Blues / Classic Rock: Distortion 4/10, Filter 3/10, Volume 7/10. Low gain with bright Filter — running the RAT2 at Distortion 4 produces a touch-sensitive, amp-like crunch that responds dynamically to picking attack. Filter at 3 (counter-clockwise) keeps treble present for single-coil articulation. Volume at 7 pushes the amp slightly, letting the amp add warmth to the RAT's hard-clipped character. Jeff Beck used similar RAT settings for his lead tone on studio sessions.
Distortion: Controls the amount of gain and clipping. Below 4 it acts more as a clean boost; 4–7 is the working hard rock and alternative range; above 7 it crosses into saturated fuzz territory where compression and sustain dominate over note definition. (Clean to Fuzz). Filter: INVERTED: turning clockwise removes treble and makes the pedal darker. At full clockwise (10) the tone is muffled and synth-like. At full counter-clockwise (0) it is buzzy and harsh. The usable range is 3–6 for most applications. Never judge the RAT2 with Filter at noon — the default noon position is far too dark for most uses. (Bright to Dark). Volume: Output level. The RAT2 can produce significantly more output than unity gain — running Volume above 7 with low Distortion is a clean boost application that many players use for solos. (Silent to Loud)
The Filter control is INVERTED — turning it clockwise makes the sound DARKER, not brighter. Counter-clockwise is brighter. Never judge the RAT2 with Filter at noon (5) as it is too dark for most applications; start with Filter at 3–4. The default noon settings on all three controls sound bad — this is normal and well-documented. The RAT2 requires deliberate dialling; the nominal 12-o'clock position on every control is not a useful starting point. Running the RAT2 into a clean tube amp produces significantly better results than into a solid-state amp. The valve power stage's natural compression and harmonic softening works with the RAT's hard clip rather than against it. A Tube Screamer or MXR Overdrive+ in front of the RAT2 (TS first, RAT second) adds midrange focus and tightens the low end — a classic combination for hard rock lead tones. At high Distortion settings, a noise gate is essential. The RAT2's high gain produces significant noise floor between notes at Distortion above 7. The Boss NS-2 or ISP Decimator after the RAT2 in the chain is the professional solution. The RAT2's hard clipping responds differently to humbuckers versus single coils — humbuckers produce a thicker, more compressed result and need lower Filter settings; single coils are brighter and need higher Filter settings to control treble.
Dave Grohl settings: Distortion 7/10, Filter 5/10, Volume 6/10. Grohl used a RAT2 in early Nirvana sessions and on early Foo Fighters recordings. The setting targets the compressed, mid-forward grunge distortion character: Distortion at 7 provides enough saturation for power chords without crossing into metal territory, Filter at 5 slightly darkens the treble buzz, Volume at 6 at unity-ish gain. The key is that Grohl ran the RAT into a clean (or slightly dirty) tube amp and let the amp add warmth to the RAT's hard clip.
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