Athena 15391 AS-P4000 400-Watt 10-inch Subwoofer (Discontinued by Manufacturer) 400-watt, 10-inch powered subwoofer for rich, powerful low-frequency reproduction Dual ports (1 bottom, 1 front) improve performance and minimize unwanted noise Down-firing orientation allows for flexible room placement and highest possible efficiency SCT rotary control for quick and easy integration with Athena home theater speakers 23 to 120 Hz frequency response; measures 11.5 x 17.5 x 18 inches (W x H x D); 1-year warranty