The [Spürr Audio] Wild Rat Distortion is a handcrafted distortion pedal that takes the circuit of the Pro Co RAT and gives it, in the words of Pedal of the Day, "a wild twist". The most visible part of that twist is the enclosure: the pedal is housed in a furry exterior, which the reviewer called "charming" and the pedal overall "aesthetically frightening". Under the fur it is a RAT-style distortion, the effect type that delivers what Pedal of the Day calls "the iconic gritty and aggressive distortion that guitarists crave".1
What it is based on
The RAT is one of the most durable distortion designs in the pedal world. GuitarPCB's technical analysis describes it simply as "a distortion pedal by Pro Co Sound"2, and Aion FX places it in a family line: "The RAT can be considered an evolution of the MXR Distortion+."3 Guitar Player's Dave Hunter, writing the RAT's history, lists its controls as "distortion, tone (changed to filter on later models) and volume"4, which is the layout the Wild Rat carries forward. The RAT has appeared in many versions over the years, including the RAT 2 with its Distortion, Filter, Volume and Mode controls5 and the FATRAT variant of the classic design6.
The controls
The Wild Rat keeps the RAT's three-knob layout. Pedal of the Day's advice to players is to "adjust the distortion, filter, and volume controls to sculpt your sound"1.
| Control | What it does |
|---|---|
| Distortion | Adjusts the amount of distortion1 |
| Filter | Adjusts the filter, the RAT's tone-shaping control1 |
| Volume | Adjusts the output volume1 |
The Filter knob is the same control that replaced the tone knob on later RAT models4, so players coming from a RAT 2 will find the layout familiar: gain first, tone in the middle, level last.
What reviewers said
Pedal of the Day reviewed the Wild Rat in August 2023 and came away impressed by both the sound and the build. The reviewer describes it as "offering an array of dirty and saturated textures to suit your playing style"1, and sums up the experience:
"we dug deep into this powerful critter to see what sounds it could make, and were very pleasantly surprised (again)"
The same review closes with a cheer to the maker: "Cheers to Spürr Audio on crafting a sonically powerful and aesthetically frightening distorted beast"1.
The Wild Rat is a small-builder pedal, handcrafted rather than mass-produced1. Availability is not the same as a mainstream production pedal like the RAT itself, so stock at dealers may vary.
Videos
Pedal of the Day
Questions
What circuit is the Spürr Audio Wild Rat based on?
The Wild Rat is based on the Pro Co RAT, the long-running distortion pedal whose controls are distortion, filter (tone on early versions) and volume. Pedal of the Day describes the Wild Rat as taking "the legendary Proco RAT basics and giving it a wild twist", with the same three-knob layout carried over. The RAT itself is widely traced back to the MXR Distortion+ as an earlier design.
What does the Filter knob do on the Wild Rat?
The Filter knob adjusts the pedal's filter control, the same tone-shaping knob found on the RAT, where it replaced an earlier tone control on later models. On the Wild Rat it works alongside the Distortion and Volume knobs: Pedal of the Day's reviewer suggests adjusting all three to sculpt your sound, from gritty and aggressive distortion through dirtier, more saturated textures.
Why does the Spürr Audio Wild Rat have a furry exterior?
The fur is an aesthetic choice by the maker. Pedal of the Day describes the pedal as handcrafted and enclosed within a "charming furry exterior", and cheers Spürr Audio on "crafting a sonically powerful and aesthetically frightening distorted beast". The fur does not change the circuit; it is what makes the RAT-based design a "wild" one.
Sources (6)
- Spürr Audio Wild Rat Distortion, Pedal of the Day, 2023-08-06
- Pro Co Rat Analysis, GuitarPCB
- Helios Vintage Distortion / Pro Co RAT, Aion FX, 2018-08-25
- From Jeff Beck and Joe Perry to Kurt Cobain and Thurston Moore, the Flexible ProCo Rat Has Star Appeal and Staying Power, GuitarPlayer (www.guitarplayer.com), 2022-12-16
- Best distortion pedals: Our top high-gain stompboxes, Guitar World, 2022-06-09
- Pro Co RAT Distortion FATRAT, Pedal of the Day, 2015-03-06
