AudioSource SW Fifteen 200-Watt Powered Subwoofer (Discontinued by Manufacturer) 200 watts total power output for loud playback and powerful dynamic slam 15-inch front-firing driver easily handles deep bass and powerful low-end audio signals 20 to 250 Hz frequency response reaches deep and also accommodates the smallest satellite speakers Variable crossover frequency, 40 to 180 Hz lets you adjust the sub for use with a range of smaller to larger speakers Auto-on signal-sensing circuitry powers the sub off when not in use