Thought I'd post a few "progress pics" for the pedal build I'm doing for Sunvalleylaw. This is the new-for-2008 BuildYourOwnClone.com Mouse vers. 2.0 kit, which is a modified clone of the famous ProCo Rat. For this new version, BYOC owner/effects wizard Keith Vonderhulls added an extremely cool new feature--a 6-way rotary switch to give the pedal 6 separate signal clipping modes. Three use the Rat's stock clip-to-ground distortion circuit, but the other three run through the pedal's feedback loop to the operational amplifier (opamp), like the Tube Screamer and its many imitator overdrives use. This gives a lesser degree of distortion with a smoother tone and less compression and sustain. The combination of the two clipping schemes makes for a very flexible pedal--basically a hybrid distortion/overdrive. Smart design!!

Of course, I couldn't just build it stock--perish the thought!! So I changed a couple of the clipping modes to give the pedal a greater range of tones. In stock form, the 6-way switch positions give the following clipping configurations:

  1. Symmetric silicon diode distortion (stock Rat mode)
  2. Symmetric red LED distortion (sometimes referred to as "Landgraff" distortion mode)
  3. Asymmetric silicon diode distortion
  4. Symmetric silicon diode overdrive
  5. Asymmetric silicon diode overdrive
  6. Symmetric MOSFET (BS170 transistor) overdrive

With four of the six modes using silicon diode combinations, I thought it would be a good idea to mix it up a bit more, so I altered positions 3, 4 and 5 to give the following:

  1. Symmetric silicon diode distortion
  2. Symmetric red LED distortion
  3. Symmetric JFET (J201 transistor) distortion
  4. Asymmetric silicon diode overdrive (1x3 1N914 diode array)
  5. Symmetric red LED overdrive
  6. Symmetric MOSFET (BS170 transistor) overdrive

That gives a mix of silicon diode, LED and transistor clipping on both the distortion and overdrive sides of the rotary switch.

I also added another popular Rat circuit modification known as the "Ruetz mod", after the guy who originated it. It's ridiculously simple, involving a SPST toggle to switch a resistor/capacitor pair in and out of the circuit. When switched out, it cuts the pedal's gain, flattens the frequency response, and gives a warmer, smoother tone--a nice counterpoint to the stock Rat's more raucous distorted sound. So, in combination with the v.2 Mouse's 6 clipping mode setting, the Ruetz switch doubles the pedal's available tones to 12. You can see what I mean about flexibility!

So with that as background on the pedal, here are a few photos taken at various points during the build (which is still underway, at this point):

PCB in process of being populated with components. Almost done, except for some of the clipping arrays, and the opamp hasn't been installed in its socket yet:



Fully assembled pedal. The top knob is the 6-way rotary, then volume on the left, gain on the right and tone on the bottom. Note the toggle on the left side down low for the Ruetz mod:



Another shot of the assembled pedal--the obligatory "gut shot". You can clearly see the solder connections (12 in a circle, 2 in the middle) for the rotary switch. The clipping sections are at upper right (1 - 3, the "distortion" clippers) and left (4 - 6 , the overdrive arrays).



More to follow....