The legendary echo machine EP-3 pre-amp as designed by Xotic. The EP Booster provides up to +20dB of boost with shimmering highs and lows. The DIP switches let you choose the boost frequencies, and EQ settings.
I built it and it sounds awesome! It instantly replaced my LPB-1 as the Xotic has more presence and nice, singing notes with lots of sustain without sounding muddy, shrill or dark.
I've used this schematic found in a project page for the PCB version of the EP Booster.
The original EP preamp was designed to run on 18v DC. Using a higher voltage than 9v DC will provide a little more boost and some added clarity with less grain.
Just make sure C4 and C7 can handle the voltage with at least 25% over capacity!
Click here to see the bill-of-materials as a list or download it as a comma separated values file (.csv).
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