High Excursion MAGMA-X Driver by Earthquake: Designed to accurately reproduce bass and sub-bass frequencies operating with extremely low distortion and impressive transient response Sound, Quality, Power: Built around a non-conventional and overbuilt motor system ensures that the subwoofer is always electrically controlled by the amplifier Durable Design: Thick poly-ether foam surround for longer life and max excursion, edge reinforced inverted dust cap for lower cone distortion, and non-pressed fiber cone for faster response and lighter mass Forced Cooled Motor: Earthquake’s Turbine Cooled Transducer (TCT) technology with perforated back plate forces drawn-in air to rotate in a vortex against the voice coil, exponentially reducing temperature by 50% Dynamic Capability: A thick 2-inch high gauss motor system of strontium cobalt with bumped back plate assists greater excursion