The 15LW1401 is a low frequency loudspeaker which sets a industry standard in 15" (380 mm) high performance transducers. The transducer has been designed for use as a low bass or sub-woofer component in either a more compact reflex, bandpass or horn loaded configuration. It provides clean, linear, undistorted low frequency reproduction at very high power levels, as part of a high power fullrange system. In its reflex configuration, it can be used in extremely compact enclosures, (65 - 130 lt) which is ideal for touring applications, including indoor and outdoor concert reinforcement systems. The high excursion capabilities of the surround and suspension system, in conjunction with the Eighteen Sound Double Silicon Spider (DSS), enable the 15LW1401 to achieve high levels of linear travel and maintain full control of the moving mass. The carbon fiber reinforced, straight-sided ribbed cone assures smooth response and exceptional strength, with maximum reliability under high mechanical stress. The 100 mm Ø copper voice coil employs the Interleaved Sandwich Voice coil (ISV) technology, in which a high strength fiberglas former carries windings on both the outer and inner surfaces to achieve a mass balanced coil. The weight of the windings are evenly distributed, providing a uniform motive drive. This, in conjunction with the use of state-of-the-art high temperature resin adhesives, results in an extremely linear motor assembly. The already low distortion and sound quality of this loudspeaker has been further improved by the Double Demodulation Rings (DDR) designed to dramatically reduce the intermodulation and harmonic distortion whilst improving the transient response. Excellent heat dissipation has been achieved by incorporating air channels between the basket and the top plate of the magnet. Further ventilation is provided using air vents in the back plate that direct air into the lower part of the voice coil gap. Maximum flux concentration and force factor is assured by the unique shape and design of the top and back plates, researched and designed using Magnetic Flux FEA CAD resource. The 15LW1401's ability to perform properly under inclement weather conditions has been achieved using an exclusive cone treatment improving pulp strength, which gives water repellent properties to both sides of the cone. In addition, a special treatment has been applied to both the top and back plates that is far more resistant to the corrosive effects of salts and oxidization than any other in use today.