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:
- Symmetric silicon diode distortion (stock Rat mode)
- Symmetric red LED distortion (sometimes referred to as "Landgraff" distortion mode)
- Asymmetric silicon diode distortion
- Symmetric silicon diode overdrive
- Asymmetric silicon diode overdrive
- 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:
- Symmetric silicon diode distortion
- Symmetric red LED distortion
- Symmetric JFET (J201 transistor) distortion
- Asymmetric silicon diode overdrive (1x3 1N914 diode array)
- Symmetric red LED overdrive
- 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....