Primal Audio has released ACID – an analog-modeled low-pass filter Rack Extension, based on the characteristic diode ladder filter design from the vintage Roland TB-303 synthesizer.

ACID extends the original filter with an envelope follower, resulting in a versatile unit capable of many types of effects, from gentle overdrive and adding some bite to samples to transforming dull synth sequences into bubbly, acidy riffs.

Here are the official audio demos:

Acid Diode Ladder Filter is available now for US $19.

Note: Primal Audio says that ACID is very demanding CPU-wise, because of the circuit modeling that is used.