Fuzz Face & Rangemaster in One! | Expresso FX Dual Ge / Si Fuzz & Ge Boost — AC125 / CV7347 / OC45
Expresso FX returns to the channel with another custom Dual Ge/Si Fuzz & Ge Boost build — this time in the chameleon color enclosure, with a completely different transistor set and a genuinely special result. Welcome back to Edge of Breakup.
In this episode the Expresso FX Custom Dual Ge/Si Fuzz & Ge Boost (Chameleon) takes center stage — featuring the Fender Custom Shop 1960 Journeyman Relic Stratocaster with Righteous Sound Pickups Opal Road Set and Emerson Custom S5B Blender 5-Way Wiring Kit and Treble Bleed, into the Benson Amps Vincent 2x12" with Scumback H75-PVC 65W speakers and Benson Tall Bird+ Reverb and Tremolo Unit via the Boss Waza Tube Amp Expander.
Reach out to Sof on Instagram DM for current inventory: https://www.instagram.com/expressofx/ Learn about the Dual Ge/Si Fuzz & Boost: https://expressofx.com/product/custom-dual-ge-si-fuzz-ge-boost-gorva-chameleon/
This is Sof's custom three-circuit pedal combining a Fuzz Face/Tone Bender hybrid fuzz with switchable germanium and silicon middle transistor, and a Rangemaster-style germanium treble boost — all in one enclosure with independent footswitches. Every transistor hand-selected NOS, zero compromise on components.
Ge Fuzz side (00:00): Three transistors — AC125 germanium in Q1, CV7347 silicon in Q2, AC125 germanium in Q3. The AC125 is a warm, full-frequency NPN germanium device from the early 1960s with smooth cleanup response and excellent harmonic complexity. The CV7347 is the military specification Mullard silicon device — grittier, more aggressive, with more upper-mid bite. Placing a silicon transistor in the middle position of a three-transistor circuit produces a hybrid character that sits between a pure germanium Fuzz Face and a pure silicon Tone Bender MKI — the warmth of the outer AC125s with the aggression of the CV7347 in the critical middle gain stage. Explored across the full opening section.
Si Fuzz side (10:05): The switch positions are compared directly — the Si Fuzz voice gives the CV7347's silicon character more prominence in the mix. Explored from 10:05 to 12:59 against the Ge Fuzz for direct comparison.
Ge Boost side (12:59): OC45 germanium transistor — the Mullard OC45, used in the earliest Dallas Rangemaster units. Authentic treble boost character with the warmth and harmonic complexity of the original circuit. Explored slamming the Benson Vincent into breakup territory.
Benson Tall Bird+ Harmonic Tremolo explored from 17:36. Fuzz stacked into Ge Boost from 19:19.
🎛️ Expresso FX: https://www.instagram.com/expressofx/ 🎸 Righteous Sound Pickups: https://www.righteoussoundpickups.com 🔊 Benson Amps: https://www.bensonamps.com/guitar-amplifiers
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🎸 Fender Custom Shop '60 Journeyman Relic Strat | Righteous Sound Opal Road Set | Emerson Custom S5B Blender + Treble Bleed 🎛️ Expresso FX Custom Dual Ge/Si Fuzz & Ge Boost (Chameleon) | AC125 + CV7347 + AC125 (Fuzz) | OC45 (Boost) | NOS Throughout | 3 Independent Circuits 🎛️ Also: Benson Tall Bird+ Harmonic Tremolo 🔊 Benson Amps Vincent 2x12" | Scumback H75-PVC 65W | Boss Waza TAE
Recording: Universal Audio Apollo x4 | Ohma Ribbon | Lauten Audio LS-208 | Royer R121 & R10 | Ableton Live 12
