CVBoard is a board designed to generate two Control Voltage (CV) signals using Arduino. This expansion module has two 3.5mm jack outputs from which it is possible to take two distinct CV signals, driven by Arduino’s digital ports, that support Pulse Width Modulation (PWM).

The idea to develop this board was born from the curiosity to experiment with how to use an Arduino to control the oscillator of a Moogerfooger Ring Modulator pedal using Control Voltage. The board, in fact, was designed to produce two 0-5V variable signals, as required by the Moog standard.

CVBoard was born with the intention of controlling the Moog pedal, but, according to the technical specifications of the A-100 system of Doepfer, it is also compatible with the standard adopted by the EuroRack modular synthesizers. In fact, in the modular systems the Control Voltage Trigger, Gate and clock signals are all defined in the range 0 / + 5V and, therefore, they are absolutely compatible with the signal produced by CVBoard. While the LFO signals are defined in the range -2.5V / 2.5V (5Vpp), so CVBoard still needs a small change (a capacitor and an extra switch should be enough) to generate LFO Control Voltage signals compatible with the standard used in the modules.

Possible application

CVBoard can be used in different ways and all, yet, to be tested and invented. The board can be used to drive hardware devices through a computer connected to Arduino. In this way, Arduino can become an interface that allows communication, through the Control Voltage, between the computer and the world of hardware tools capable of responding to this type of analog signal. It is, therefore, interesting to experiment a digital control approach of “analog” devices, as already widely experimented in the 60s and 70s in the early stages of computer music research.

An other possibility is to program Arduino to execute algorithmic composition programs and therefore operate without a computer to create sequencers or control voltage generation tools made through precise compositional hypotheses. Finally, the possibility of experimenting with the use and integration of sensors and systems typical of Physical Computing in the field of modular synthesizers is also very fascinating.

So, CVBoard allows to experiment new ways to interact with modular synths. It is possible to use any kind of sensors or programming for any kind of strange signal.

This video: New creative way to play with a modular synth shows a first test we did to control a modular synth using an ultrasonic distance sensor attached to Arduino. CVBoard and Arduino allows to transform the distance measured by the sensor into a signal capable of modifying the sound produced by the modular synth.

An other demo here CVBoard: Arduino Control Voltage.

More info here: http://www.artislab.it/en/arduino-control-voltage-cvboard/