The 15" FSL-1530R01-08 8 ohm woofer features a FEA optimised ferrite magnet motor, 3" voice coil, cloth surround, paper cone, a vented yoke for motor cooling, and a high strength stamped steel frame. Kevlar loaded non-pressed paper cone to help dampen and control cone resonance. The multi-roll surround and spider have been optimized to reduce distortion over the excursion range of this transducer.