The basic size of the Bowers and Wilkins MM-1 (10cm square by 17cm high) is no great surprise, and the look doesn't give much away.

The first hint that this is something a little clever is the inclusion of a USB cable: yes, this speaker system is computer-oriented to the point of having a USB digital input, plus a single analogue input on a mini-jack connector.

Indeed, it's very heavily digital, having also a digital amplifier and some Digital Signal Processing (DSP) which is claimed, rather vaguely, to keep music 'sounding rich and detail, no matter how loud you play it'. Some sort of unheralded 'loudness control'? We'll come back to that...

The right speaker includes the electronics and connects to the left via a cable, which, if there's slack, can be partly wound out of sight under the left speaker. There's even a remote control, capable of operating as a transport control for suitable computer software.

As luck would have it, this system arrived last of the four, and so had some high standards to live up to when we first plugged it in. Let's just say it opened our eyes to new standards of attainment possible from miniature hi-fi .

We don't even want to know whether that DSP is doing some loudness control: the fact is that at any level setting the sound is just astonishingly clear, well balanced and detailed. The deepest bass isn't really there, but even with such torture tracks as full-on church organ, one only notices that at the start.

Dispersion is stunning, the sound being highly consistent almost anywhere roughly in front of the speakers and the imaging is excellent.

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