The FruitFX Pedals Melon Cube Synth Fuzz is a synth fuzz pedal that turns a guitar into a square wave, producing everything from thick walls of fuzz to old school video game style leads1. It is a pulse width modulator (PWM), a circuit more commonly associated with synthesizers, applied here to the guitar signal12. Pedal of the Day reported in May 2026 that it has become FruitFX Pedals' best-selling pedal3.
What it does to a guitar signal
Delicious Audio's Paolo De Gregorio described the result as "a radical tonal recasting that sits uniquely between a harmonically dense, aggressive fuzz and the chiptune-esque timbres of early digital synthesis"2. In other words, the pedal does not layer a synth on top of the guitar the way a tracking synth pedal such as the BOSS SY-1 does. It reshapes the guitar's own signal into a square wave, so the sound follows the player's picking and fretting directly.
Pedal of the Day's reviewer argued that in a crowded market, the Melon Cube manages to stand out above the usual stuff, both sonically and aesthetically overall1.
The controls
The pedal has five knobs that work together to produce a wide range of sounds1.
| Control | What it does |
|---|---|
| Shape | Governs the square wave's width, the core parameter defining its harmonic character2 |
| Juice | Acts as a voltage starve, allowing the effect to collapse into a more conventional fuzz texture2 |
| Gate | Creates short bursts of sound with dead silence on the other end1 |
| Level | Output level2 |
| Tone | Standard tone control, described by Pedal of the Day as smooth12 |
The Shape and Juice knobs work well together, according to Pedal of the Day, "letting you jump into a deep sonic rabbit hole"1. Because Juice works as a voltage starve, backing it off is the route to a more conventional fuzz texture, while the Shape knob defines the square wave's harmonic character at the other end2.
The Gate functionality here is awesome, giving you the ability to create short bursts of sound with dead silence on the other end.
Where it sits among the alternatives
Players looking at the synth fuzz corner of the market will find the Melon Cube sits closer to a fuzz circuit than to tracking synth pedals like the Electro-Harmonix Micro Synthesizer or the Source Audio C4 Synth, since it transforms the guitar signal itself rather than generating a separate synth voice. FruitFX Pedals later released a spin-off, the Space Cube Phase Locked Loop (PLL) Fuzz, which Pedal of the Day reviewed in May 20263.
Videos
FruitFX
Working Class Music
Pedal of the Day
Questions
What does the Juice knob do on the Melon Cube?
According to Delicious Audio, the Juice knob acts as a voltage starve, allowing the effect to collapse into a more conventional fuzz texture. Pedal of the Day found that the Shape and Juice knobs work well together, letting players explore a wide range of sounds from the same pedal.
Can the Melon Cube sound like a regular fuzz?
Yes, within limits. Delicious Audio reports that the Juice knob works as a voltage starve, which lets the effect collapse into a more conventional fuzz texture. At its other extreme the pedal produces chiptune-like square wave tones, so it covers ground between a harmonically dense fuzz and early digital synth sounds.
What does the Gate control do on the Melon Cube?
Pedal of the Day's reviewer described the Gate functionality as awesome, giving the player the ability to create short bursts of sound with dead silence on the other end. It is one of five knobs on the pedal, alongside Level, Tone, Shape and Juice.
Is the Melon Cube a PWM pedal?
Yes. Pedal of the Day calls it a pulse width modulator, a circuit more commonly associated with synthesizers, and Delicious Audio likewise describes it as a pulse-width modulator pedal for guitar that applies its transformation to the instrument's signal.
Sources (3)
- FruitFX Pedals Melon Cube Synth Fuzz, Pedal of the Day, 2025-12-13
- New Pedal: FruitFX Pedals Melon Cube Synth Fuzz, Delicious Audio, 2025-12-16
- FruitFX Pedals Space Cube Phase Locked Loop (PLL) Fuzz, Pedal of the Day, 2026-05-19
