Speaker System Z313 features a convenient control pod, room-filling sound, compact subwoofer, & easy setup. The control pod makes it easy to control volume & headphone controls. You can fill your room with big, balanced sound (25 watts). The compact subwoofer fits into tight spaces & delivers deeper bass. To set up, simply connect the speakers to the subwoofer & plug the subwoofer into your computer. Total RMS power is 25 watts (RMS). Frequency response is 48 Hz to 20 kHz (+/- 3dB). The subwoofer measures 8-2/3" wide x 6" long x 9" high (22cm x 15cm by 22-4/5cm). Each satellite measures 3-1/4" wide x 3-1/2" long x 5-3/4" high (8-1/10cm x 8-9/10cm x 14-2/3cm).