The hardware

 

The main processing in the EEG-synth is done on a Raspberry Pi, an inexpensive microcomputer (under $40). However, you can use and develop the EEGsynth on any PC, Mac or Linux computer. We typically use the affordable open-source hardware of the OpenBCI project for electrophysiological recordings. However, the EEGsynth can also interface with state-of-the-art commercial scientific equipment. We are able to do this by using the FieldTrip realtime buffer which supports many acquisition devices. If you are interested in developing your own code, make sure to familiarize yourself with the FieldTrip realtime buffer.

To control analogue and digital synthesizers, the EEGsynth can send out CV/gate, MIDI, Open Sound Control, DMX512, Art-Net, and interface with several commercial devices (see software). It is thereby extremely flexible and able to interface with most sound as well as visual performance equipment. Furthermore, we use the network transparent Redis database, allowing the output of the EEGsynth to be easily imported in software for e.g. game development.

Robert Oostenveld designed and build our own USB-to-CV/gate converter, which uses an Arduino and some ICs (some soldering and drilling required) to generate continuous voltages. The first USB-to-CV/gate version had one CV/gate channel and was able to output up to approximately 5 volts. An improved version has four channels and can generate 0-10 volts. The schematics have been made with the EAGLE PCB design software. Also included below is the bill of materials (BOM) with links to component vendors. Follow the links for more details and code for testing.

Single channel USB-to-CV/Gate convertor

2015-10-03 16.35.52

 

 

Four channel USB-to-CV/Gate convertor

2015-10-18 13.11.43