The TOA SR-C15B is a passive 15" bass-reflex subwoofer engineered specifically for integration with the SR-C8L and SR-C8S line array speakers. It is intended for professional installed and touring applications where a full-range line array system must extend low-frequency reproduction into the 40 Hz range. The SR-C15B is optimized to operate with TOA's optional DP-SP3 digital speaker processor, which applies the recommended parameters for frequency response and crossover alignment. Without the processor, frequency response and crossover performance will differ from published specifications. Built for flown deployment, the enclosure features M8 threaded steel plates that accept optional accessory brackets for suspension or stand mounting, including the optional SR-RF8 rigging frame. Input flexibility is provided through both M4 screw terminal connections and two Neutrik NL4 sockets, accommodating a variety of install and touring cable configurations. At 90 lbs, this is a purpose-built component for integrators and production teams assembling a complete SR-C series line array system rather than a standalone general-purpose subwoofer.