Legendary analog low-pass VCF module for Eurorack. An authentically vintage-sounding reproduction of the circuits from the "Modular 55, 35 & 15" series from the 1970s, used by the world's most famous pop, rock, and jazz musicians in their shows. Now musicians can build their very own, unique synthesizer that fits into a standard Eurorack case at a very affordable price. Mix and match specific modules to create your personal, one-of-a-kind synthesizer that complements the music you play, or go all out and fill a room from floor to ceiling with modules that fulfill every synthesizer enthusiast's wildest dream. The 904A Controlled Low Pass Filter features a cutoff frequency control that allows you to decide which frequencies to attenuate. The resulting frequency is determined by this control, giving you the ability to shape your sound with a twist.