In any home theater system, the driving force is the main left and right speakers. The S1.8 with its 8 inch Kevlar cone woofer, 3 inch soft dome midrange, and 1.125 inch high-power soft dome tweeter was designed for this function and performs comparable to surrounds in a larger system. Because of S4X technology, thie S1.8iw can be combined with any of our main and surround speakers, be they in-wall, on-wall, or free-standing to build a home theater system. S4X also provides greatly increased control over frequency response, phase, and impedance, resulting in superior performance and imaging.