Yes, it's SUPPOSED to sound like that: my modified version of the Synthrotek DIRT filter

 While I personally refuse to make the jump to the Eurorack/500/modular gear universe, I am not against appropriating some of the more common sounds that exist there. Especially the ones that can be easily modified to work with a negative center +9v DC power supply.

I found this one on Synthrotek's site - the schematic I have included is lifted from the build doc for this modular filter kit that they sell under the name "DIRT". It's technically a low-pass filter with a whole lot of noisy possibilities. The resonance and bias are highly interactive with each other AND the cutoff control.

I modified their layout slightly, subbing a 1n4001 for the polarity protection diode (they call for a 1n4148 - which has a similar forward voltage drop) as well as eliminating the battery clip, adding an input pull-down resistor (1m to ground on the input) and a master volume potentiometer.

I tested the CV input using an Electro Faustus Dual Oscillator, and it made this thing stutter and bubble like crazy.

Once again - all credit is due to Synthrotek for the design + schematic on this one and if you use Eurorack units, you should buy a kit from them and build it. But if you want to make a super-noisy, unpredictable low pass filter for use in stompbox format - I can't recommend this one enough.