The AI010 Eurorack Attenuator is a 2hp dual passive attenuator with switched jacks that allow the attenuator to also work as a multuple.
The top-most input is normalled to the second attenuator knob and the third attenuator input.
Control voltage is a wonderful way to add expression to a modular patch, and controlling that control voltage is crucial to being able to dial in that expression.
A passive eurorack attenuator is a simple un-powered circuit using only resistive elements (usually a potentiometer) to reduce voltage. Rotating the potentiometer will change the output from 0V to 100% of the input without distorting the shape of the incoming voltage. These are simple and primitive, but effective and important methods of controlling voltage, be it the input to a Filter, or the Linear Frequency Modulation input on an Oscillator.