Secret Preamp

BOOSTER

The Chase Tone Secret Preamp is a pedal-format recreation of the vintage 1970s solid-state Maestro EP-3 preamp circuit. It reproduces the EP-3’s characteristic warm, harmonically rich, “3D” tone — enhancing clarity, touch sensitivity and dynamic feel without drastically changing the core sound. The pedal offers a 3-way mode switch (Bright / Dark / Mid) to emulate early-, late-, or hybrid-era EP-3 tones, plus a volume control calibrated for unity gain, slight boost or transparent EQ-on output. It runs on 9 V DC (center-negative), internally steps the voltage up to ~22 V to match the original preamp’s operating conditions, and delivers enough headroom to push amps or clean up effects. Designed to be “always-on,” it’s often placed at the end of the signal chain to polish tone, fatten fuzz/drive pedals or restore clarity after long effect chains. The chassis is pedalboard-friendly, built to fit standard pedalboard layouts and use top-mount or rear-mount jacks for convenience.