Plan B Model 12 filter module

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"This is a great filter that responds nicely to control voltage and gate inputs because of the vactrols used in the design. Basically, the decay is nonlinear and more like what an acoustic instrument does than other filters that don't have vactrols. This allows for more "realistic" sounds such as classic Buchla-esque woody percussion sounds.

The sound is smooth, but can be overdriven and you can see on the input how I labelled '7' on it to tell me when the pot setting starts registering distortion. This is the first version of the Model 12, so I had to mod it and add a switch to get the "overdrive" function that later batches came with stock. The mod consisted of wiring a resistor across one of the vactrols (see photo of the interior) with a switch on the front panel."

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