DESCRIPTION * 1.75-inch compression driver with Polymide-Kapton dome and reinforced ribs for 10 times the durability of previous designs * 15-inch woofer tested with over 200 hours of continuous signal at extreme levels * Up to 131dB SPL * 2,100W Class D Bi-amplification 45Hz?20kHz frequency response * True Resistance Waveguide technology represents a clean stereo image with minimal high frequency distortion * Proprietary FiRPHASE technology for superior phase control of mid-low frequencies * Bass Motion Control technology for increased woofer motion without phase behavior changes * M-Brace cabinet design made from polypropylene composite material with improved damping and mechanical stress resistance * Solid aluminum heat exchanger with no moving parts improves energy efficiency and removes the need for a cooling fan Brand RCF