Befaco – FX Boy – Full DIY Kit

£259.00 (Excl. VAT)

A Multi FX module based on game carts!

Includes 7 carts from Befaco, Instruo, Feedback, Making Sound Machines, Tesseract, TouellSkouarn, and XOR!

Only 1 left in stock


FxBoy is a multi-FX module designed in collaboration with several talented manufacturers. The different effects are physically hosted in hot-swappable game cartridges and each one is designed by a different manufacturer. All effect carts come already pre-assembled.

Each effect features CV control over two different parameters (X & Y) as well as CV over the dry/wet mix. There is also a built-in CV controllable four band EQ which can be switched to either pre-FX or post FX. All effects also have two modes of operation: A and B. What these two modes do depends on the individual cartridge design. See the user manual below for more details.

The included FX cartridges are:

  • Trash (Befaco) – is a harmonic distortion that combines both clipping and folding flavours. Modes A and B will select between aggressive and more aggressive flavours!
  • Micro Phaser (Instruo) – is three cascaded all-pass filters, a built-in LFO and a saturator in the feedback path. The purpose for this cartridge is to completely f&%k your phase up!
  • Flanger (Feedback) – cartridge has two modes: classic flanger with LFO speed and a Delay with time, both with feedback
  • Analog Wavefolder (Making Sound Machines) – is a classic West Coast Synthesis circuit, designed to add harmonically related overtones. This cartridge is excellent at adding rich harmonics to a basic waveform, and cool distortion to complex signals like drum sounds. Its circuit can produce characteristic timbres similar to pulse-width and frequency modulation.
  • AVMA (Tesseract) – is a bipolar VCA with one switchable wavefolder stage followed by an analog frequency reducer. The VCA gain is x2, it can be used with ±5V oscillator signals at the CV input for ring modulation effect.
  • Eskuara (TouellSkouarn) – is a feedback fuzz/overdrive circuit, created to distort and make noise. The cartridge combines fuzzes and overdrive while incorporating feedback control for added experimentation and allows musicians to create a wide range of distorted and saturated tones, with the added ability to manipulate sustain and feedback for unique sonic textures.
  • FxGirl (XOR) – is a digital double effect module: Delay + Granularizer


  • CV control over all parameters and Dry/wet
  • CV controllable four-band EQ, routable post or pre-effect.
  • Selector for two different flavours of each cart.
  • Open specifications to design your own carts
  • Hot swap for all carts. (A tiny pop can occur depending on the cartridge design)


  • Width: 12 HP
  • Depth: 35 mm (including power connector)
  • Power Consumption: +12V: 125mA, -12V: 100mA (plus cartridge current draw)
  • Aluminium front panel.
  • Designed and assembled in Barcelona.

FX Boy – Build Document | User Manual 

WARNING: NEVER ATTEMPT TO PLUG ANY FX BOY CARTRIDGE INTO ANY DEVICE OTHER THAN FX BOY, NOR PLUG CARTRIDGES FROM OTHER PLATFORMS INTO FX BOY, EVEN IF THEY LOOK SIMILAR. It will cause unpredictable and permanent harm to either FX BOY, the cartridges, or any third-party electronic devices you connect the cards to. Befaco and Thonk are not responsible for any damage caused to yourself, the FX BOY, the FX BOY cartridges, or any other third-party device by not following this advice.




Additional information

Weight 0.646 kg
HP Size

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