The Doepfer A-106-6 is an XP multimode voltage controlled filter module for the Eurorack A-100 system based on the classic Oberheim Xpander filter. Featuring 15 types of filter, up to 8 types can be used simultaneously. There are manual controls over audio input level, allowing you to drive the filter for a warm and harmonic sound, frequency cut-off range, frequency control voltage, Q control voltage and Q control.