PiRAT Distortion

PiRAT is a ProCo Rat stomp box emulation, redesigned for Eurorack, based on the amazing Rodent VST from Valdemar Erlingsson.

The original VST includes:

• a very nice sounding emulation (based on in-depth ProCo Rat circuit analysis);
• 3 classic parameters (Gain / Tone and Level);
• various mods inspired from the hardware (turbo, ruetz, ...).

PiRAT inherits the circuit emulation from Rodent and adds its own flavor to it:

• stereo signal path (can act like a simple stereo VCA when bypass is enabled);
• dry / wet mixer to cross-fade between clean / overdrive / distortion;
• mixer to blend between silicon and diode clipping in hard clipping (turbo) mode;
• optional noise gate (based on the wonderful NoiseInvader VST).

PiRAT is written using DaisySP, and can run on:

• VCV Rack 2;
• Daisy Patch SM (patch.init Eurorack module);
• Versio (World of Versio);
• Legio (World of Legio).

The Daisy Patch SM firmware adds:

• customizable threshold / release for the noise gate;
• envelope follower (both raw signal and a gate with adjustable threshold);
• trigger to gate (with variable length).

The Versio firmware adds:

• customizable threshold / release for the noise gate;
• envelope modulation of gain / filter (with attenuverters).

The Legio firmware adds:

• customizable threshold / release for the noise gate.

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Installation

PiRAT firmware can be directly downloaded on GitHub (or compiled from sources).

It can be flashed using Electro-smith Daisy web programmer or Noise Engineering portal.

Warning: flashing your module with PiRAT will be done at your own risk! That said, Daisy based modules are able to recover if anything goes wrong during the flash procedure. So it should always be possible to restart it and/or flash an official firmware back.

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Compilation

Dependencies

linux (ubuntu)

$ sudo apt-get install build-essential git cmake gcc-arm-none-eabi binutils-arm-none-eabi dfu-util jq zstd libgl-dev

macOS

Require Xcode and MacPorts (or any alternative).

$ sudo port install cmake dfu-util jq zstd

The arm-none-eabi compilation tools are currently broken on MacPorts.

Official ARM packages can be used instead (arm-gnu-toolchain-12.3.rel1-darwin-arm64-arm-none-eabi.pkg has been successfully tested). Tools are installed in a non-standard directory (ex: /Applications/ArmGNUToolchain/12.3.rel1/arm-none-eabi/bin) that need to be exported in the PATH environment variable.

Configure

From the root directory:

$ mkdir build
$ cd build
$ cmake ..

Build

From the build directory created above:

VCV Rack

$ make
$ make install

Daisy Patch SM

$ make firmware
$ make flash

Versio

$ make firmware_versio
$ make flash_versio

Legio

$ make firmware_legio
$ make flash_legio

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License

PiRAT is licensed under 2-Clause BSD, a free and open-source license. For more information, please see BSD-2-Clause.