Polk Audio TSx 220B Bookshelf Speaker - Black TSx Series bi-laminate composite driver cones, tuned perfectly with our Dynamic Balance process, produce smooth, natural sound. They are lightweight, but super stiff, with exceptional damping, for high efficiency and low distortion. Front-firing tuned port smooths low frequency blending, for surprisingly full-bodied deep bass response from a bookshelf loudspeaker. All Polk loudspeakers are timbre-matched within their series, designed with the same components throughout, to achieve seamless speaker-to-speaker blending effects in multi-channel systems. Gold-plated, professional-style 5-way binding posts, for the most secure connection options. 5 YEARS parts and warranty