Polk Audio AM4095-A Monitor 40 Series II Bookshelf Speaker 1-inch (25mm) fabric/polymer composite Dynamic Balance dome tweeter with powerful neodymium magnet structure delivers clear and detailed high frequency response for realistic reproduction of vocals and instruments 5 1/4-inch Bi-laminate composite dynamic balance drivers are lightweight and stiff with good damping for high efficiency, excellent bass and lower distortion Multiple small-diameter driver design delivers wide dispersion, better mid-range, and more detailed bass response for an open, "box-less" three-dimensional sound Non-resonant all-MDF enclosure construction with 3/4-inch thick baffles ensures cleaner, clearer, more lifelike sound quality. (Tower models feature additional front to-back and side-to-side internal bracing for further reduced resonance.) Crossovers use Mylar bypass capacitors for more detailed high frequencies