The Unsound Circuitry Kato Glitch Fuzz is a dual-circuit fuzz pedal from an Icelandic builder, combining an exceedingly loud germanium fuzz with a separate dual-mode glitch effect1. Delicious Audio presents it as "the most violent nine-volt sound mangler in existence"1, and the site later added it to its roundup of the best crazy, weird and unusual fuzz pedals12.
The fuzz side
The fuzz is built on four low-gain, Russian-made germanium transistors, with an unstable oscillation circuit activated by the footswitch on the right2. Delicious Audio's Paolo De Gregorio describes the signal path simply: the Gain knob does what is expected of it, thickening the fuzz at higher levels, and the resulting tone can be pushed further via the Volume knob, situated on the top left at the end of the fuzz part of the circuit1.
The glitch side
The glitch side is, at its core, a PLL circuit that generates a square wave1. It is activated via the left footswitch, but not separately from the fuzz1. Guitar Pedal X describes the layout as having separate bypass and Activate PLL footswitches3.
Its controls:
| Control | What it does |
|---|---|
| Depth | Sets the amount of low frequencies going into the glitch side, basically a high pass filter1 |
| Drift | Spans Tracking to Divebomb3 |
| Amok / Drone | Amok is glitchy and fragmented; Drone is more continuous3 |
In Amok mode the square wave is rather unruly; in Drone mode it is more predictable1. Guitar Pedal X sums up the PLL side as additive only, delivering tracking, divebomb, glitchy/fragmented, drone, and low-end variation, while the Octave Fuzz works independently3. The fuzz side also carries Gain and Sensitivity (Input Gain Sensitivity) controls3.
How the two circuits work together
The two circuits are placed in parallel with each other, rather than one feeding the other, so the volume knobs will mix the two signals1. That matters in practice: because the PLL side is additive only, you can run the fuzz alone, the glitch alone, or blend them, and the character of the fuzz is not filtered through the glitch circuit13.
What reviewers said
Guitar Pedal X's Stefan Karlsson reviewed the pedal in December 2023 and was warm about the sound while critical of the size3:
"I love enormous sound that emanates from this fuzz. Circuit-wise it's right up my street - and I always love when there..."
He praised the enormous sound and ample range, particularly the Volume / Level and Gain sound and range3. His main reservation was the enclosure: it is oversized, similar in size to the Laowiz Cyst Mode and the Fuzzrocious Electric Ocean3.
The Kato Glitch Fuzz is priced in euros at €185 as of December 20233. Players comparing it with US-made pedals should note that no US dollar list price is published.
Where it sits
The Kato belongs to the small family of fuzzes built around instability and digital-style artifacts rather than pure clipping. Unsound Circuitry's range also includes the Hyper Pozzum V2, and players drawn to the Kato's square-wave character may also want to look at synth and octave and pitch pedals, which work in related territory1.
Videos
UNSOUND CIRCUITRY
Pedal Experiments
Boring Gear Reviews
Questions
Can the Kato Glitch Fuzz be used as a plain fuzz?
Yes. The fuzz and glitch circuits sit in parallel rather than one feeding the other, and the PLL side is additive only, so the fuzz works on its own. Guitar Pedal X notes that the Octave Fuzz works independently, with the glitch side engaged separately via its own footswitch. The volume knobs mix the two circuits together.
What is the difference between Amok and Drone mode?
The two modes shape how the PLL circuit's square wave behaves. Delicious Audio describes Amok mode as rather unruly, while Drone mode makes the square wave more predictable. Guitar Pedal X characterises the same switch as Amok, which is glitchy and fragmented, versus Drone, which is more continuous.
What power does the Kato Glitch Fuzz need?
The pedal runs on nine volts. Delicious Audio introduces it as the most violent nine-volt sound mangler in existence, and that nine-volt figure is the power requirement given for the pedal. No current draw figure is published.
What does the Divebomb part of the Drift knob do?
The Drift control on the PLL side spans from Tracking to Divebomb, according to Guitar Pedal X. It sits alongside the Amok/Drone mode switch and the Depth control, which sets how much low frequency reaches the glitch circuit, shaping how the square-wave effect follows and shifts against your playing.
How big is the Kato Glitch Fuzz enclosure?
Guitar Pedal X's reviewer describes it as an oversized enclosure, similar in size to the Laowiz Cyst Mode and the Fuzzrocious Electric Ocean. He flagged the size as a drawback of an otherwise well-received pedal, so players planning a tight pedalboard should account for the extra room it takes.
Sources (3)
- Unsound Circuitry Kato Glitch Fuzz, Delicious Audio, 2023-12-12
- The Best Crazy, Weird, And Unusual Fuzz Pedals In 2024, Delicious Audio, 2024-10-24
- Guitar Pedal X, Guitar Pedal X, 2023-12-12
