The OPA-151SA is a powered 15-inch subwoofer that combines a powerful One Systems woofer, Two 1,000-watt peak power amplifiers and flexible user-adjustable DSP into a small-sized enclosure. Its two European-designed amplifiers provide power for the subwoofer as well as for other OPA Series full-range speaker models. The OPA-151SA is equipped with factory presets for the OPALine-82 and other OPA models, plus it has three memory slots for storing various setups. OPA-NET software, included with the subwoofer, provides access to a full range of performance parameters including input and output delays, full parametric EQs, dynamics processing and much more from any PC. Its RS-485 connections allow system control and monitoring as well as level and program changes. The OPA-151SA has a 15-inch woofer with a 4-inch voice coil delivers sub-40 Hz response. The enclosure is made of 13-ply birch plywood covered in tough PowerCoat and is equipped with an M20-sized pole socket so speakers can be suspended above the subwoofer. The OPA-151SA provides system power, sophisticated control and rock-solid deep bass.