Earthquake's Supernova MKIV Series of powered subwoofers delivers an amazing combination of high performance and efficiency. Its brilliant design overcomes the limitations known from conventional closed and ported designs that prevent radical excursion, deep response and high dB. The active driver used in the MKIV is designed for accurate reproduction of bass and sub-bass frequencies. Its thermally pressed poly-ether foam surround allows high excursion without deformation. The Symmetrically Loaded Audio Passive System (SLAPS) lets one amplifier produce the output of two woofers, reducing your power consumption and electricity bill. The 450-watt amplifier has a multitude of user friendly features that put you in control. The MKIV has advanced technology that reproduces low recordings at high dB, putting you directly in the center of the movie set.