Polk Audio PSW450 Powered SubWoofer (Discontinued by Manufacturer) 12 Direct Radiating Woofer Overall bass frequency range - 25 Hz - 160Hz Adjustable crossover control helps adjust for smooth operation with your other speakers - Range - 80Hz - 160Hz Built-in amplifier delivers 150 watts Continuous Average Output into 4 ohm load over a bandwidth of 30 - 200 Hz with &lt;1% THD Dual flared ports for low distortion