The Function f(x) Octavus is an octave-up fuzz in a mini pedal format. The maker describes it as its take on the vintage Tycobrahe Octavia circuit, a fuzz and octave divider pedal that produced an octave-up effect, built by one of the pioneering effects builders of the 1970s1. Function f(x) says that if you want "that Jimi / Monterey Pop Festival kind of sound, this is a good fit in a tiny footprint"1.
What it does
An octave-up fuzz combines fuzz distortion with an octave divider, adding a note one octave above what you play. The original Tycobrahe Octavia, described by GuitarPlayer as "a fuzz/octave divider pedal that provided an octave-up effect," came from the same 1970s builder behind the Parapedal and Pedalflanger2. The Octavus puts that style of circuit into a modern mini pedal. Function f(x) notes that it uses all current-production parts to ensure reliability and consistency1.
Controls and power
The pedal keeps things simple with two knobs:
| Control | What it does |
|---|---|
| Level | Output volume |
| Fuzz | Amount of fuzz |
Power is 9V DC, which Function f(x) calls the industry standard, with a 10mA current draw1. That is light enough for any standard pedalboard supply.
Size and availability
The Octavus is a mini pedal: the enclosure measures 3.6 x 1.5 x 1.2 inches (92.5 x 38.5 x 31 mm) and it weighs 7 oz (198 g), with laser-etched artwork on the enclosure1. It is listed on Function f(x)'s mini pedals page alongside the maker's other compact designs31, and Function f(x) also classifies it as a "Tychobrahe Octavia Variant" in its range3.
The Octavus carries a list price of $179.00 USD1.
Function f(x) builds a wider line of fuzzes, including the Clusterfuzz, the maker's first product, as well as the Clusterfuzz Jr., Gate Crasher and Cannon Dual Fuzz. For more circuits in this family, see the site's Fuzz Pedals and Octave & Pitch Pedals pages.
Questions
Is the Function f(x) Octavus true bypass?
Yes. Function f(x) specifies true bypass mechanical switching on the Octavus, so when the pedal is off, your guitar's signal passes straight through without any buffering or tone change from the circuit.
What is the Function f(x) Octavus based on?
The Octavus is Function f(x)'s take on the vintage Tycobrahe Octavia circuit, a fuzz and octave divider pedal that produced an octave-up effect. The original Octavia dates back to the 1970s era of pioneering effects builders.
What power supply does the Octavus need?
The Octavus runs on 9V DC, which Function f(x) describes as the industry standard, and draws 10mA. A standard center-negative pedal supply handles it easily.
How big is the Function f(x) Octavus?
The enclosure measures 3.6 x 1.5 x 1.2 inches (92.5 x 38.5 x 31 mm) and the pedal weighs 7 oz (198 g), making it a mini pedal that fits a small footprint on a pedalboard.
Is the Function f(x) Octavus still available?
The maker's page is the place to watch for restocks.
Sources (3)
- Octavus - Tychobrahe Octavia Variant - Tiny and Ferocious - Function f(x), Function f(x), 2026-09-30
- Six Pioneering Effects Builders of the 1970s, GuitarPlayer, 2022-05-26
- Clusterfuzz, Function f(x), 2026-07-17
