This subwoofer has a classic sweet-sounding, 'hi-fi' analogue class AB amplifier in its guts, plus the suddenly trendy driver from Peerless called the XXLS 12. (The very same driver was used in the XTZ subwoofer).

In this far smaller enclosure, the honest paper pulp-coned woofer is sealed in rather than differentially ported like the XTZ, and is far easier to set up as a result. It is a downfiring design in a box that would suit a 10-incher. It's certainly priced like a product of this size, with its rivals list having to be drawn from competing subs of up to £200 more in price!

Our sample came in a shiny black finish and with not only a nicely made Speakon plug-on-a-wire to hook to your speaker outputs, but also a high-quality mono phono cord with plugs that are clearly handmade.

The feet that hold the woofer boundary-loaded off the floor can have either PTFE studs or spikes fixed into their bushings, and the sub's controls are brilliant. For one, you get a separate gain pot for each of the high and low level inputs, because you are meant to use both. Use of a simultaneous speaker level input makes sure you get to amplify all the bass.

BK electronics xxls400df

Also, you can switch the lowpass crossover filter out of circuit just for the phono or low-level input alone. This means you can use pure direct mode and feed the woofer with LFE you filter at your decoder/AVR, while the full range stuff sent to the speakers can feed bass into your woofer, unimpeded by mids and highs.

In action, BK's sub is deliciously musical. It is tight and tracks a bass line with taut precision and almost no overhang. The opening sequence of the Blu-ray of Hancock was handled brilliantly, too: gunfire, big American trucks crashing into cop cars and helicopter rotor blades scything the air. But cut to Hancock drunk on a bench and the BK still delivers the bluesey bass line behind him, even deeper.

Accurate and authoritative, this punches way beyond its weight and, bizarrely, out of its price point, too