after building my Deacy amplifier it was obviously missing a vital part - the treble booster Brian May used
however instead of just building up the rangemaster (which is a fine booster) I thought I would make my own from scratch - first of all I didn't want to go for a Germanium Transistor as is most common with these kinds of guitar process pedals because Brian actually had a treble booster based around a silicon transistor (BC182) which was what I was going to use initially but then I thought "nah - try and be at least a little bit original" so I went to my component bins and found a 2N2484 - well I found a 2S733 first but I couldn't find an online seller of them which would be pretty important for anyone else who builds this - so I built it around the 2N2484 which is readily available from places like farnell.
anyway when building this kind of thing there isn't so much leeway on how you build it, it's essentially an amplifier and a filter type of thing, the designs choices you get to make are the component values and in my case I wanted to keep the nice chime type treble boost but allow a bit more bass through
I also put in a gain pot. you may notice if you look at the schematic that there is a capacitor going to the gain pot from the output line. the reason for this is that an audio signal is AC however when you sweep a pot wiper from ground you get noise in the form of DC which presents itself as horrible low frequency crackling noise, using a capacitor between the output and the pot stops this as a capacitor decouples DC but leaves AC in tact.
the less resistance to ground there is, the less output you have however I have used a 10ohm resistor to limit the volume reduction so the pot sweeps from clean to overdriven
it sounds ace anyway
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