Enter the Behringer 904B VOTLAGE CONTROLLED HIGH PASS FILTER Module. A vintage-sounding authentic reproduction of the circuitry from the “Modular 55 & 35” Series used by the world’s most famous pop, rock and jazz musicians for their shows. Now, musicians can build their very own, unique, synthesizer that can fit in a standard Eurorack case for a very affordable price. Mix and match specific modules to create your personal, unique synth to complement the music you play or go all out and fill a room, from floor to ceiling, with modules that’ll fulfill any synth geek’s wildest dream.