Vintage-Accurate 1970s Solid-State Maestro Echoplex Preamp

The Chase Tone Secret Preamp is a faithful recreation of the most sought-after Echoplex EP-3 preamp circuits—renowned for their ability to enhance guitar tone in subtle but powerful ways.

In the late '60s and early '70s, Echoplex tape delays transitioned from tube-based designs to solid-state models like the EP-3. While not all EP-3s were created equal—some degraded the signal or sounded lifeless—a select few became legendary for their ability to fatten tone, add harmonic complexity, and introduce a subtle phase shift that brought out musical mids and highs.

Even when the delay was bypassed, players like Page, EVH, and Gilmour noticed something special happened when their signal passed through the EP-3 preamp. That “secret sauce” became a foundational part of many iconic tones.

Over a decade ago, Kyle Chase set out to capture the magic of those legendary EP-3 units. The result is the Secret Preamp—painstakingly tuned using vintage-spec JFETs and components to deliver consistent, musical results.

Key Applications:

• Use it as a transparent boost to enhance harmonic content and touch sensitivity.

• Add depth and dimensionality—your “normal” tone, but bigger and better.

• Place it before or after an analog delay for authentic Echoplex-style coloration.

• Run it after a vintage-style fuzz to recreate the sound of a cranked amp pushing a fuzz box.

Chase Tone Secret Preamp Features

• Faithful recreation of the most desirable EP-3 solid-state preamps

• Switchable EQ voicings: Bright (early EP-3), Dark (later EP-3), and Mid (hybrid voicing)

• Works equally well at unity gain or as a subtle boost

• Vintage 1970s-spec JFETs, cherry-picked for optimal response

• Accurate vintage-value resistors and capacitors

• True Bypass switching

• Power: 9V DC (150mA)

• Dimensions: 4.5" x 2.5" x 1.5"