Expresso FX's Custom Ge Fuzz / Ge Boost / Octave Up is a custom-built pedal that combines three circuits in one box: a germanium fuzz, a germanium boost, and an octave up effect. Each can be used on its own or stacked with the others, so the pedal can cover everything from a straight boost to full fuzz-and-octave textures1. It is built by hand by designer Sofiane Tebboune under the Expresso FX name1.
The Expresso FX Custom Ge Fuzz / Ge Boost / Octave Up is priced at £ 449.002. As a custom-built unit, availability depends on the maker's build schedule.
The three circuits
The fuzz stage comes first in the chain and is built around a matched pair of Mullard CV7005 germanium transistors1. The germanium boost that follows is built around a Mullard AC107 germanium transistor1. The last circuit is the Octave Up effect, which Expresso FX describes as usable in conjunction with the two other circuits, or individually1. The whole pedal is populated with NOS Mullard C280 Tropical Fish capacitors1.
The controls
The germanium boost circuit is fitted with a 7-way rotary switch providing 7 tonal settings, running from treble-focused, to mid-focused, and to bass-focused options1. That gives the boost stage a voice selector rather than a single fixed tone, so it can be shaped to sit behind a bright or a dark amp.
| Circuit | Key control | What it does |
|---|---|---|
| Germanium Boost | 7-way rotary switch | Selects 7 tonal settings from treble-focused to mid-focused to bass-focused1 |
| Germanium Fuzz | Matched Mullard CV7005 pair | Fuzz stage built around hand selected NOS transistors1 |
| Octave Up | Individual or combined use | Runs alone or stacked with the fuzz and boost1 |
How it compares within the Expresso FX range
Expresso FX also builds the Custom Dual Ge/Si Fuzz & Ge Boost, a related custom dual-circuit pedal with a Ge/Si Fuzz on the right side and a Ge Boost on the left3. Where the pedal on this page uses an all-germanium fuzz built on a matched pair of CV7005s, the Dual Ge/Si mixes germanium and silicon stages, with a Mullard AC188 in Q2 on the fuzz side and a Mullard OC45 germanium transistor on the boost side3. Both pedals share the same approach to the boost stage: each carries a 7-way rotary switch for selecting a range of tones from treble-focused, to mid-focused, or to more bass-focused tones4. The Dual Ge/Si is also described by the maker as fully hand wired and true bypass3. Players who want a single-box germanium fuzz and boost with an octave up added will look at this pedal; those who want to switch between germanium and silicon fuzz characters have the dual-circuit alternative.
For a boost-only option from the same maker in a smaller format, Expresso FX also lists the Germanium Boost Mini and the Germanium Boost "Mojo Edition", and the broader category is covered on Boost Pedals. Related effect types are covered on Fuzz Pedals and Octave & Pitch Pedals.
Build details
- Genuine Hammond enclosure finished in Dark Gray Sparkle1
- Alpha foot switches1
- True bypass switching1
- NOS Mullard C280 Tropical Fish capacitors1
- Hand selected NOS germanium transistors1
- 3 years warranty1
Videos
Edge of Breakup 🎥 Guitars, Pickups, Amps & Pedals and Jules Leyhe
Questions
Can the octave up be used on its own?
Yes. Expresso FX describes the Octave Up circuit as an effect that can be used in conjunction with the germanium fuzz and germanium boost, or individually. That means you can run it as a standalone octave up on your board, or stack it with the other two circuits in the pedal for combined fuzz, boost and octave textures.
Is the Expresso FX Ge Fuzz / Ge Boost / Octave Up true bypass?
Yes. The maker's product page lists the pedal as true bypass, so when it is switched off your signal passes through without loading from the fuzz, boost or octave circuits.
Who designed the Expresso FX Ge Fuzz / Ge Boost / Octave Up?
The pedal is designed by Sofiane Tebboune of Expresso FX, who builds the company's custom pedals by hand and describes the components and circuits on the maker's product pages.
Which germanium transistors does it use?
The pedal uses hand selected NOS germanium transistors: a matched pair of Mullard CV7005 in the germanium fuzz circuit and a Mullard AC107 in the germanium boost circuit. The pedal also carries NOS Mullard C280 Tropical Fish capacitors.
Sources (4)
- Custom Ge Fuzz / Ge Boost / Octave Up, Expresso FX, 2024-07-18
- Custom Ge Fuzz / Ge Boost / Octave Up, Expresso FX, 2024-07-18
- Custom Dual Ge/Si Fuzz & Ge Boost, Expresso FX, 2024-09-15
- Custom Dual Ge/Si Fuzz & Ge Boost, Expresso FX, 2024-09-15
