QM 212AS is a compact, powered, 2 x 12" multi-chamber sub-woofer system. It has all the advantages the passive QM 212S with the addition of integrated electronics. A power amplifier (800W), electronic crossovers, equalization and speaker protection is all integrated into the QM 212AS amplifier module. Adjustable low pass filter for the sub bass amplifier allows the user to change the mid bass roll off. High pass line level output from the stereo electronic cross-over allows the user to interface powered speakers at a variety of cross-over frequencies or as full range line level outputs. An ideal bass partner for not just the Q-motion satellite boxes, but any quality installed or portable sound reinforcement system where compact high output cub bass is required.