This is an unusually intelligently designed eight-way distribution block. Mounting those sockets the 'wrong' way up is ideal for those who use anything thicker and less flexible than the basic PVC mains lead, while using both sides of the tapered profile seems a sensible optimisation of space. Eight sockets should cater for most systems.

The sockets themselves are MK's best, unswitched, and usefully treated with Caig contact enhancer. Good quality Kimber wire is used to link them to the 16A IEC inlet, for which you'll need to buy a special mains lead as an extra: we used a Russ Andrews Reference PowerKord (£84).

What really justifies the price, however, is the inclusion inside the housing of a Russ Andrews 'Ultra Purifier' filter circuit.

This unit, available separately for £255, is a 'shunt' filter that has no components between the supply and your kit, and it features not only the usual capacitors (lots of them!) but an unusual spike-clamping component that costs a lot and claims to be particularly effective in preventing over-voltage spikes from getting through.

We failed to find any spikes for it to clamp, but we did prove that the Ultra Purifier cuts noise on the mains above about 5kHz.

Sonically it had a useful effect on various source and amplifier components we tried, improving image focus by a significant degree and seeming to reduce the level of 'hash' around the sound. There's no effect on tonality, but the precision of instruments, particularly those with transient-rich sound, is audibly improved. Overall, a recommended upgrade. Richard Black