My first goal when designing the Evil Twin mk II was to make the fuzz intensity of the blue box based octave fuzz adjustable. In the original pedal, and in the RSH pedals, it is always maxed out, and it has to be this way for the primitive circuit to divide down the frequency and generate the weird monophonic octave-down tone. With less fuzz intensity, the tracking would fail.
But in collaboration with my brilliant Danish engineering partner, I found a way. With the Evil Twin mk II you can back down the fuzz and still have the octave-down tone, with all it's glitchy goodness. I am pretty sure we are the first ever to have succesfully done this modification to the blue box circuit.
Apart from adding this key-feature, we did not mess a lot with the old blue box, because I think it looses its primitive lo-fi charm, if you attempt to clean it up too much and improve tracking and gating etc. In other words, it still sounds sick. And evil.
I always got complaints about the effects of the Rowland S. Howard pedal being too weak in output level, and it is true that they are not very loud, because that's how the vintage circuits are designed. But we fixed the loudness issue in the Evil Twin mk II by adding a recovery gain stage to both circuits, so now they are VERY loud.
We also added a tone control to each circuit. In the octave fuzz circuit it serves as substitute for the 'C11 mod' switch inside the RSH-03 pedal, covering the range between the dark and muffled sounding unmodded circuit and the bright 'C11' mod.
In the distortion circuit the tone control is a treble filter, bleeding off the high frequencies. Turned all the way up, the tone control has no effect (no filtering), making the tone similar to the original, tone control-less vintage distortion+ circuit.
The distortion section of the Evil Twin mk II can be preset to six different clipping configurations via switches inside the pedal:
One of the things I believe has contributed to the RSH pedal's continued succes through ten years, is that the two effects in the pedals stacks so incredibly well. It's like the octave fuzz circuit becomes much more alive in combination with the distortion - which adds interesting overtones to the artificial, synth-like octave-down tones.
This quality lives on in the Evil Twin mk II. Only a little more care has to be taken in dialling it in, because both sections of the pedal has become louder and wilder. Due to the added recovery gain stage, the octave fuzz circuit can now push the input stage of the distortion circuit much harder, making more extreme effects possible.
This also means there can be more craziness going on. The RSH was a wild beast, and I have had many emails from confused customers who could not understand all the weird clicking noises and stuff going on when the pedal was idling with both effects on and the guitar wide open. Well, there's more of that now, because all those little noises can be amplified even more. A lot more, actually. The Evil Twin is not a nice pedal. It's a wild and crazy creative tool, that you have to learn to master. So be warned.
Having said that, the Evil Twin mk II is far more than an experimentalist’s noise tool. Both sides offers a very wide range of sounds, and it can also be more subtle and mild than the RSH-03, because of the possibility of turning down the fuzz intensity of the octave fuzz, and the different clipping options of the distortion section. The pure germanium clipping of the RSH and original distortion+ pedals clips more than the default Ge/MOSFET clipping, making subtle edge-of-breakup crunch effects much easier to dial in with the Evil Twin.
I ship the pedals with the octave fuzz set to the standard two octaves down. The ‘fat switch’ of the distortion is default set to ‘ON’, and The 6dB boost switch is off (this is intended for use when the pedal is set to pure germanium clipping, which has less loudness).