thunderaxe
New member
So the version of the Expandora that I want to build is essentially the same as the Aion Effects Dynamo, with the two switches replaced by a "Drive" knob instead. And I think I want to add the Bass Pot described in this thread as well (instead of the bass switch on the Dynamo). Since I was ordering a couple of PedalPCBs anyway I decided in my infinite wisdom as someone who has never built a pedal before but is an incurable tinkerer and also a cheapskate who hates paying extra for shipping, that I would just add the Pandora's Box to my order and then mod it. The particulars of replacing the switched resistors with a pot isn't my question, I pretty much just copied & pasted the resistor and pot from the Dynamo into the Pandora's Box circuit, my question is more this -- does replacing the switches with a Drive knob kind of make the Gain knob redundant? I understand that in theory they're doing different things -- as I understand it (and do please correct my if I'm wrong, and you may have to explain like I'm 5 because I am a complete noob), the switched resistors in the Opto part of the circuit decide how much the Opto can reduce the amount of gain going into the clipping stage, and when they're removed entirely for Forbidden Mode you just get an ungodly amount of gain slamming into the front end of the OpAmp causing it to freak out into insane fuzz and self-oscillation. The good stuff. Anyway, with that essentially controlling the gain, what role does the normal Gain knob play anymore? Is it just like a micro adjustment and the Drive knob is the Macro? If so, does it make sense to keep it? Can it be done away with?
