Cluster is Toppobrillo's take on the classic Buchla 257 voltage processor with useful modern features added! 

The original Buchla 257 was a CV processor that would sum an offset with another signal (with bipolar input control) and also Sum these with a voltage controlled crossfader (and if you left one side empty it would double as a VCA.)  This allowed it to function as attenuator, offset, crossfader, mixer, and VCA all in one.

Toppobrillo has added voltage control to the attenuverter channel, allowing use as a bipolar VCA.   The Offset channel is now bipolar and features a CV input, which when patched will bypass the offset and act as an additional input to the mixer.  An inverted SUM has been added alongside the regular SUM output, and each section now has it's own output, where patching an output removes it from the SUM, allowing each section to be broken off and used seperately if desired (so if you don't need the offset it can be an extra channel for mixing or just a spare bipolar attenuator etc.)

Cluster is a precision 8HP processing toolbox that can sit anywhere in a system. It has 3 independent sections that can be used individually or taken as a whole. Up to 4 signals can be mixed and there is also a complementary sum output. Potentiometers are center-detented for easy tactile centering. Signal path is high bandwidth, low noise and low offset- and is well-suited for both audio and control signals.

A classic modular CV toolbox made even more useful! With clever use it can be used as a pair of VCAs, Ring Mod, Rectifier, AND logic, VC Switch, Crossfader, Mixer, and so much more!

Specifications:

8HP

+30 @ +12V

-25mA @ -12V

20mm deep