The JBL / Selenium 15SWS1000 is a high power 15" Professional Subwoofer specially designed to reproduce sound at the very low end of the audio spectrum.  This new design is capable of handling up to 1000 W RMS.  A bumped and undercut T yoke assures a minimum of magnetic rectification (off centering) and a compatible maximum displacement (XMAS).  The magnet assembly was designed through the assistance of a finite element analysis (FEA) software in order to ensure optimization.  The 4 layers copper voice coil, using over 80 g of copper, is wound on a fiberglass composite former, twice the thickness of typical formers, to drive the moving assembly through great rigidity.  The non pressed long fiber pulp cone has the necessary mass and stiffness to withstand the tremendous accelerating forces required, and is precisely centered by 2 counter balancing, distortion cancelling, polyester cotton fibre spiders.  A triple cooling system consisting of a large diameter center hole surrounded by 6 smaller holes (directly cooling the gap) and 6 frame windows (cooling the air trapped between the 2 spiders) are responsible for an efficient heat transfer mechanism.  A highly reinforced aluminum injected frame is effective in absorbing mechanical shocks and acts as a heat sink without interfering through the magnetic field.