Coupling, Cold Clipping, and Attenuation

Now might be a good time to talk about coupling capacitors. They connect different circuits together by blocking the high voltage DC but allowing your AC guitar signal to pass through. Just like the tone stack capacitors, the choice of capacitor value will effect the frequency range allowed to move on to the next stages. C12 .022μF below is an example of a capacitor used to connect the V2B gain stage to the rest of the circuit.

Let’s start talking about gain stages that have a more distorted or overdriven sound. A great

example is the cold clipper. This was made popular by the first Marshall amps with a Master Volume and Soldano’s more aggressive take on that. See here:

At first glance, this looks a lot like the gain stage we looked at earlier but look at R2 10K. That’s a lot more resistance than we saw earlier! More resistance means a less efficient gain stage which news less gain, but the. Fun part is it’s so low that it actually clips the signal very easily resulting in some nice smooth overdriven sound. Soldano amps use a 39K resistor here for even more aggressive clipping. (So does JUDGE)

Another important part of this circuit is attenuating the new giant clipped signal. That’s a fancy way of saying bring it back down. We are talking about way too much gain at this point. R9 470K knocks down the signal quite a bit while C6 470p capacitor allows some higher frequencies to pass through undisturbed. This values can be adjusted to suit your taste. What we

end up with is a gain stage that brings the signal way up, brings it up even more while also clipping it in a nice musical way, and then bringing it back down to make it more manageable for the next stages.