The XTAL audio pole dancer filter is a 12HP eurorack format filter

The XTAL audio pole dancer filter is a 12HP eurorack format filter with the following features:

Simultaneous 2 pole and 4 pole low pass outputs
Filter self-oscillates through entire audio range
Second out of phase 1 pole VCF with dedicated CV input and frequency control
Filters are combined at both outputs to allow for low, band, high pass and phaser-like responses
1 v/oct input accurate over 5 octaves (modulates both filters simultaneously)
Bipolar (attenuverting) exponential input (modulates primary filter only)
Unipolar linear FM input (modulates primary filter only)
Unipolar input attenuator