The Pioneer TS-WX126B 12 in. Compact Preloaded Subwoofer Enclosure is non-amplified for system flexibility. The voice coil cooling system uses the subwoofer motor structure as a heatsink to lower the operating temperature of the voice coil, increasing power handling and enhancing reliability. The voice coil is overhung for high power handling and the magnet pole is extended for improved linearity. The enclosure and subwoofer are specially matched and tuned for high performance.