D Series subwoofer drivers were developed for professional car audio installations and car audio competitions. Each driver features the same design principles found in all D Series loudspeaker drivers and uses the very best in electro acoustic technology. High power oversized voice coils to provide maximum dynamic output with minimal distortion. Bass is both powerful and tight and gives balanced and accurate output without compromising sound quality. Further features include a long stoke linear design with a high performance suspension system comprised of high performance rubber surround and durable spider. The driver gives extremely high sound pressure capabilities with proper phase coherence. The systems high flux magnetic circuit built into a durable cast iron frame provides a strong driving force with minimal resonance. Cones are pressed using a composite Kevlar fiber / paper pulp mixture and pressed under high pressure and temperature to give optimal rigidity and minimal mass. The special cone material gives an accurate tonal response while preserving a natural sound. Bass can be both heard and felt.