The Cusack Music Project 34 Selenium Rectifier Pre/Drive is an overdrive, boost and preamp pedal whose clipping character comes from an unusual part: a selenium rectifier, a component type that predates germanium and silicon and dates back to the early 1930s1. Cusack Music describes it as usable as a boost, a preamp, a bit of compression, or a light overdrive, depending on how the gain is set2.
The name is a chemistry reference. Selenium's atomic number is 34, so "Project 34" points straight at the element at the center of the circuit1. The pedal ships in a Malbec Red Metallic powder coat finish1.
What it does and how it is controlled
The Project 34 is a Pre/Drive pedal: one circuit that can serve as a clean-ish boost in front of an amp, a preamp shaping the amp's front end, a light compressor feel, or a low-gain overdrive2. Cusack Music says the selenium rectifier at its heart gives it characteristics more akin to a small tube amp than the "diode and transistor fizzle fade" of typical clipping stages1.
The control set is simple:
| Control | What it does |
|---|---|
| Level | Sets the output volume |
| Gain | Sets the amount of drive, from boost through light overdrive |
| Tone | Shapes the treble response |
| Low-End Contour | Three-way switch with More, Neutral and Most positions, shaping how much low end passes through4 |
The Low-End Contour switch is the control that reaches the different amp-style voicings. Guitar Pedal X's reviewer, Stefan Karlsson, found that through its controls the pedal can reach Fender, Marshall and Vox voicings, a bit of Matamp, and several more4.
Selenium rectifiers and a limited run
A selenium rectifier is an early rectifier technology, a component that converts alternating current to direct current. Cusack Music notes that selenium rectifiers go back to pre-germanium times and were first introduced in the early 1930s1. In the guitar world they were last used as rectifiers in older amps, such as the 1950s tweeds, before being phased out in the 1960s as the industry turned to silicon and tube rectifiers3. Today they are usually relegated to just a few larger industrial and military applications1.
That history is why the Project 34 is scarce. Karlsson reported that the selenium rectifiers used are pretty rare 1930s components in incredibly short supply, so the pedals will inevitably be a limited edition run4. Cusack Music's own page echoes the urgency: "Pick one up while you can, once you find how the P-34 works for your tone you'll likely never want to be without one!"1
This is not Cusack Music's first pedal built around selenium. The Project 34 Selenium Rectifier Pre/Drive is based on rare 1930s selenium rectifiers, components the maker says are in incredibly short supply1.
B-stock Project 34 units sell for $195, $45 below the $240 list price. Cusack Music says B-stock may have minor scratches, paint chips, overspray, misprints or other small finishing blemishes, but the pedals are in perfect working condition and come with the original box, box goodies, and warranty2.
What reviewers said
Guitar Pedal X reviewed the pedal at its April 2024 pre-order launch. Stefan Karlsson called it a standout among the year's many classic overdrive clones4:
"it's a genuine nice surprise when we encounter something wholly different, and that is spectacularly great sounding"
He described its tone profile as carrying a massive hint of Vox alongside a touch of cocked wah, with a richly textured breakup character, "verily sounding like it's loaded with tubes and other primo amp components"4. The pedal also made Guitar Pedal X's roundup of the best new boost and overdrive pedals of 2024, listed at $2405.
Videos
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Questions
What is a selenium rectifier?
A selenium rectifier is an early type of rectifier, a component that converts alternating current to direct current. It predates germanium and silicon parts and was first introduced in the early 1930s. In the guitar world it was last used as the rectifier in older amps such as 1950s tweeds, before the industry moved to silicon and tube rectifiers in the 1960s. Today it survives mostly in a few industrial and military applications.
What does the Low-End Contour switch do on the Project 34?
The Low-End Contour switch is a three-way toggle with More, Neutral and Most positions. It shapes how much low end the pedal passes, so a player can keep the bass tight at higher gain settings or let more bottom end through for a fuller, looser feel. It sits alongside the Level, Gain and Tone knobs as the pedal's fourth control.
Is the Cusack Project 34 a limited edition?
Guitar Pedal X reported in April 2024 that production was expected to be a limited edition run, because the 1930s selenium rectifiers at the pedal's heart are rare and in incredibly short supply. Cusack Music's own product page urges buyers to pick one up while they can. A previous selenium-based pedal, the Screamer Fuzz Selenium, was a run of just 20 that sold out immediately.
How much does the Cusack Project 34 cost?
The Project 34 lists at $240. It went up for pre-order at that price in April 2024, and Cusack Music's product page still shows $240 as of October 2026. B-stock units, which may have minor finishing blemishes but are in perfect working condition and come with the original box and warranty, sell for $195.
What amp voicings can the Project 34 reach?
Guitar Pedal X's reviewer found the pedal's controls can reach Fender, Marshall and Vox voicings, a bit of Matamp, and several more. He also noted a massive hint of Vox in its tone profile alongside a touch of cocked wah, with a rich breakup character that he described as sounding like it is loaded with tubes.
Sources (5)
- Project 34 Selenium Preamp and Drive Pedal, Cusack Music
- Project 34 Pre/Drive, B-Stock Discount, Cusack Music
- Project 34, RockBoard PedalPedia, 2026
- Guitar Pedal X, Guitar Pedal X, 2024-04-10
- Guitar Pedal X, Guitar Pedal X, 2024-12-16
