Klipsch Reference Series RT-10d Digitally Controlled Subwoofer - BLACK Maximum Acoustic Output - 119dB @ 30Hz 1/8 Space, 1m / Frequency Response 22-120Hz +/-3dB Amplifier Power - FTC Rated Power - 700 Watts Continuous @ &lt;2% THD / Dynamic Power - 1600 Watts Drive Components - Ultra-High-Excursion 10 (25.4cm) Cerametallic Cone, Front-Firing WooferDual Ultra-High-Excursion 10 (25.4cm) Cerametallic Cone, Rear-Firing Passive Radiators Amplifier Type - BASH digital hybrid Enclosure Type - Bass-Reflex Via Dual Rear-Firing Passive Radiators