If you want a home entertainment subwoofer that delivers apocalyptic bass extension with zero distortion, consider Model 209.

Powered by a 1000W amp with DSP-based equalisation and volume, phase, polarity and crossover parameters adjustable by remote control, the 450mm (18in.) cone has a double radial magnet, a unique dual suspension system, and the effective cabinet volume is virtually doubled by KEF’s Acoustic Compliance Enhancement technology.