Preoccupation with mains-borne intrusions is not a condition to which I'm enslaved. Simply put, I live in the countryside, my listening room has separate, dedicated mains supplies wired with politically-correct cabling and sockets, and the AC distribution lump for the neighbourhood - located in my back garden! - provides a constant 241V to 246V supply. And while I wouldn't say that the system is immune to mains accessories, neither would I ignore any opportunity to improve my lot.

Isol-8's Nic Poulson, late of Trilogy and Isotek (for whom he developed their original line of mains filters), suggested that I try his new PowerStation, feeling that I might find its improvements more vivid than those of mere mains filtering systems. Like those from PS Audio, Accuphase and precious few others, the PowerStation an actual mains regenerator, not a simple filter, which should ensure an absolutely perfect 240V/50Hz supply ... or whatever else you might specify. Where it differs from most is that it has a truly separate 'channel' for two components, rather than a shared set-up.

Nic said that his goal was, 'to get as close to the perfect power supply as is practically possible. Power supply quality is a key influence in any system's performance. Passive filtering can achieve only so much by working with what is already there. But by locally generating a perfect mains waveform, consistently free from distortion and noise, a system can have total freedom from the many compromises our common power grid imposes.'

To this end, he developed a unit that supplies two independent channels of 'clean, pure regenerated power [that] will transform even the highest quality source components.' In the PowerStation, 'noisy mains power is transformed into relatively clean DC (or Direct Current) and is used to supply power amplifiers that produce a pure and precise sine wave. The output is proportioned to suit the requirements of the equipment powered.'

Inside the PowerStation are three microcontrollers to generate and oversee the operation of two 'ultra stable waveforms of purity (0.05%THD) that are simply unobtainable from your domestic supply.' Thus, the unit will feed two components, e.g. a preamp and a CD player, with their own direct, high peak current supplies, via a pair of three-pin mains outlets on the back of the unit, with no risk of 'cross contamination.'

Nic has provided each channel with frequency adjustability from press buttons on the front panel, in five steps of 50, 60, 67.5, 81 and 100Hz, to allow a component's power supply to take advantage of a higher 'refresh' rate. I have to admit that I was nervous about playing around with frequency, but the gains were clearly audible, including even lower noise and a sense of added precision. Every single device I tried, including the Audio Research PH5 phono amp, Musical Fidelity Nu-Vista preamp, and Musical Fidelity kW25 CD players sounded sharper, faster and better controlled with a step up to a mere 60Hz. As Nic explained, 'At 100Hz, a linear power supply connected to the PowerStation will have effectively double its normal capacity, leading to further gains in sound quality.'

Output up to 100W per channel is provided by the PowerStation; this might be enough to allow the driving of small power amplifiers, but that could be pushing it. Nic recommends that users stick solely with source components, preamps, tuners and the like, as I did. The amplifiers in the PowerStation are specially designed for mains regeneration, and are coupled to their loads through bespoke output transformers.

Housed in a substantial chassis with two heatsink-festooned 'wings' connected by a central control section, the PowerStation even looks like an expensive power amplifier. Like the equally handsome regenerators from PS Audio and Accuphase, you won't want to hide it. Hell, if you did, you'd be unable to see the informative digital read-out and LED tell-tales. It monitors input voltage and frequency, amplifier temperature and output frequency, and there's a 'night mode' to dim this to the minimum.

Here we have the sort of device that reveals its worth immediately, and canny retailers will find ways to set up demos with two identical sources to show via A/B switching how much benefit you can gain from a cleaner, more precise power supply. The most obvious gain is a reduction in noise and 'hash,' but other benefits include the aforementioned precision, greater clarity and a tangible gain in control in the lower registers. Best of all, unlike some mains filters that can strip sound of its nuances, there simply is no down-side.

£2195 might seem steep for what is an accessory, not a 'performing' component. Nic, though, puts it into context: 'In value for money terms, the unit should be regarded not as a mere mains purifier, but as if it were a high quality, 250W per channel power amp, with two precision microprocessor oscillators and two output transformers thrown in for good measure!'

My advice? Given the size of the investment, it's worth every penny, but only if you've sorted out your key components first. The PowerStation is what you add to a system to extract everything that it can offer, not as a substitute for a lesser component. If you have a finely-tuned set-up and you want to ensure that its working of its best, borrow a PowerStation from a retailer. Here's betting that you won't be able to give it back.

Specification:
Input voltage 220, 230 or 240 Volts +/- 10%
Input frequency 48-62Hz
Stand by power requirement 6VA
Maximum power requirement 350VA
Output voltage 230 Volts +/- 1.5% (60Hz)
Output frequencies 50, 60, 67.5, 81 and 100HZ
Output frequency accuracy 0.05%
Rated output power 100VA per channel (resistive load)
Maximum operational temperature 62 degrees centigrade
Remote in 8-24 Volts AC or DC on pins 1&2
Size 445x145x420mm (WHD)
Weight 19Kg

Isol-8 Teknologies 020 8856 8856
www.isol-8.co.uk/