Erica Synths has announced that it is discontinuing its legacy DIY eurorack projects, and making them open source so that they can still be available to synthesists that want to DIY their modules.

The collection of projects includes an all-in-one acid bassline synth voice, BBD delay, MIDI-to-CV module and enough designs that once could build up a complete system.

Erica Synths plans to introduce a new collection of educational DIY kits for simple and affordable Eurorack modules, in collaboration with Riga Technical University. They plan to announced the new line in Autumn 2020.

The open source projects include:

• Bassline – all in one synth voice for acid basslines and drones
• BBD delay/flanger – all analogue effects unit based on V3205 BBD IC Delay – tape and digital delay unit with tap tempo, tempo sync, reverse, hold and add functions
• Dual VCA – Polivoks architecture inspired dual VCA, rare Russian differential op-amps are now replaced with AS3330
• Envelope – recreation of Polivoks envelope generator with loop and end of attack functions
• MIDI-CV – Polivoks functionality inspired dual MIDI-CV converter with glide function
• Mixer – simple 3 chanel audio mixer
• Modulator – Polivoks functionality inspired LFO, noise and S&H module
• Output – Output module with headphone amplifier
• Polivoks VCF – authentic recreation of the Polivoks VCF
• Swamp – their take on the Wogglebug module
• VCO3 – Polivoks inspired VCO with nice extra – VCO Sync input

The projects are available on Github. Each project folder contains complete information and files to build a module: schematics, Gerber files for a front panel, Gerber files for PCBs, BOMs, component placement with values and designators and assembly manuals.

By making these projects open source, Erica Synths accepts third party use for personal, educational or commercial purposes. Since they are available as free and open source projects, Erica Synths will not provide technical support.