Well Rats - A Pro Co Rat Clone!

Introduced in 1978, the Pro Co Rat distortion pedal became a staple of 1980s hard rock and heavy metal music. While still in production, the Rat has gone through several iterations, though the basic circuit really hasn't changed much. One of the first pedals I picked up was a new production Pro Co Rat pedal, but Aion FX has a version under the name "Helios" which not only adds some additional functionality, but uses a standard 125B enclosure making laying out the increasingly precious geography on my pedal board a bit easier!

As you can see from the image above of the PCB, the Rat circuit is not incredibly intricate, and it is based on an op-amp gain stage. I even managed to score an original LM308N op-amp from Pedalhacker for this build. You'll also likely notice the open electrolytic capacitor slot above the red film capacitor below the red LEDs. This is an optional capacitor which can be replaced with a slightly different rating film capacitor based on the build notes (the aforementioned red film capacitor below the electrolytic silkscreen). As film capacitors tend to have slightly better audio properties, I went with the film for this build.

For the enclosure on this one I decided to have a little fun. If you've read my other blog, you know I'm into miniature wargaming. In the fantasy version of the Warhammer franchise of games, there is a race of ratmen known as the Skaven. As this is a Rat clone pedal, I decided to have a little fun with that theme. Vermintide is a series of video games set in the Warhammer world with the ratmen as primary antagonists.

I vector traced a logo from online for the main pedal name. I then found the font that is used in a lot of the older Warhammer rulebooks to use for all of the labels on the dials. The front and rear decals are the standard "Steggo" decals. These, once again, were all printed on my laser printer on clear waterslide decal paper. The LED is a yellow-green color, which sort of mimics the "Warpstone" that the ratmen in world are so fond of.

Like the mainstream pedal on which it's based, the Helios is a good tunable distortion pedal. I honestly so far like the extra control I get over the OEM pedal, though I really need to line both of them up and do an exhaustive sound test between the two. That being said, this build has taken the place of the original on the pedal board for the time being.