Multifunction Dual Phototransistor VCA

EARTH VCA is a dual VCA built around a very common part called an opto-isolator which is most often used in modern switch-mode power supplies. Opto-isolators use a phototransistor as the output instead of the photoresistor used in vactrols. When used in a VCA, they have a sweet, slightly rounded over tone, are very quiet when closed and respond to CV much more quickly than vactrols. They also produce a smooth asymmetrical distortion that can be controlled by adding the audio signal to a dc offset. The VCA has an exponential response and a DC coupled signal path that allows for use with control signals.

The link and invert buttons add the level and CV inputs from the top 'earth' VCA and pass them down to the lower 'satellite' VCA. This makes multiple functions possible including stereo VCA, VC crossfade, VC pan, pseudo sidechain compression and VC mix. The top VCA's input and output are normalled and mixed respectively into the bottom vca's input and output making it easy to use the pair in various ways without external mults or mixers.

http://www.coppertracesmusic.com/eurorack.html

• 16 mA +12V
• 35 mA -12V
• 0 mA 5V
• 40 mm Depth

No info about availability.