The Alto Professional TS18S offers a rock-solid solution for bass-deficient PA systems. This powered subwoofer's high-efficiency Class D amplifier delivers a hefty 2,500 watts of rafter-shaking low end via a premium 18-inch driver with a 3-inch high-temperature voice coil. The TS18S integrates effortlessly into any live sound setup, boasting dual combo inputs and XLR outputs, dual XLR thru ports for linking, user-selectable EQ presets, and a phase alignment switch. This active sub is eminently roadworthy as well, sporting a rugged, internally braced, front-ported MDF cabinet with an integrated 36mm pole socket, a mark-resistant splatter-spray finish, and comprehensive protection circuitry. The Alto Professional TS18S is a surefire method for upgrading an underperforming sound reinforcement system.