The Vaderin Pedals HP-X Harmonic Percolator is a fuzz/distortion pedal built around the circuit of the original Harmonic Percolator from Interfax. Pedal of the Day describes it as "a vintage circuit, modernized for today's differing climates", designed to capture the original's signature even-order harmonics saturation without compromising stability or volume1.
How it works
The HP-X follows the Harmonic Percolator recipe but swaps the transistors: it "features silicon transistors, instead of the classic germanium, in the PNP position", a change the review frames as modernizing a vintage circuit so it behaves consistently today1. The design aims to keep the even-order harmonics saturation the original was known for while holding stability and volume steady1.
A three-way toggle selects the clipping character:
| Switch position | What it does |
|---|---|
| Symmetrical Silicon | Silicon diode clipping, symmetrical |
| Asymmetrical Germanium | Germanium diode clipping, asymmetrical |
| Diode lift | Lifts the diodes out of the circuit for all-transistor distortion |
The three options are described by Pedal of the Day as "3 diode clipping options: Symmetrical Silicon, Asymmetrical Germanium or a diode lift for all transistor distortion"1.
Controls
The pedal keeps things to two knobs:
What reviewers said
Pedal of the Day's reviewer came away enthusiastic, calling it "This orange gem" (the enclosure is orange) and writing "We love this thing", recommending hearing the pedal in their demo. The review points to "years, maybe decades, of wonderful, fuzzy playability"1.
Videos
Noise Generator
collector//emitter
ambienttrash
Sources (1)
- Vaderin Pedals HP-X Harmonic Percolator, Pedal of the Day, 2021-10-21
