A powerful, accurate subwoofer adds weight, depth and intensity to the 3D sound image, and the output of KEF's new slot port design has been increased by 10dB at 30Hz. The integral 250 Watt amplifier drives a forward-firing long-throw 250mm (10) bass unit with exceptionally low distortion characteristics for clean, well defined low frequency response throughout the room. This generously extended bass can be fine-tuned to suit your set-up and preferences, with a variable slope switch to ensure seamless integration with the satellite speakers, a ground lift switch to prevent hum and switchable cinema/music modes to provide extra punch for reproducing the full impact of movie special effects.