The Electro-Voice TX2181 is a dual subwoofer system that is designed to add high-output, high-impact bass response to the TX2152 loudspeaker system. The TX2181 can move tremendous amounts of air, thanks to dual EVS-18S high excursion woofers, a well braced enclosure, and a low distortion port design. The EVS-18S woofers feature 4-layer voice coils and cast frames for high power handling and maximum durability. The TX2181 is designed to be used with a processor and a dedicated amplifier channel in a biamp configuration.