HiFi Critic Mains Conditioning Group Test – Opinion by Steve Elford

In the latest issue of HiFi Critic, Julian Musgrave reports on an extensive group test of mains conditioners from five manufacturers. It takes a considerable amount of work to carry out such a review, and like all reviews it is very dependent on the reviewers personal tastes and experience and the systems they use to do the testing. The review cover's these issues off pretty well by using two very different systems and adding an additional listener into the process. 

From our point of view of course, we were delighted to see that the HiRez Taga and HiRez Balanced Taga shone through with the best performance. And we like how Julian provided a very sensible cost verses performance comparison where again the two Tagas did very well. What was so interesting though, was how the listening results seemed to be an unexpected surprise to him. And I think there are a few important reasons for that. 

First, mains conditioning is not really about the 50 Hz AC supply. It's more about all the other signals that are on the mains, AND the noise from other household electronics and the hifi system itself. Understanding this also requires some understanding of how noise effects our hifi, actually inside the main components, an area we have studied in great depth. The truth here is that it doesn't take much noise to start to noticeably degrade performance in a hifi – particularly on the grounds. The trick is to actually reduce that noise without introducing other problems like slowing current delivery.

It's also about the problem of vibration being carried around the mains loom. Compared to our competitors, we apply far more extensive anti-vibration techniques to help lower this effect – and this really shows in the performance of the Tagas. And with the Balanced Taga, careful design and quality of the balanced transformer is particularly important. This expensive item, bespoke made for us in the UK, has gone through many design changes to get right. 

So about the review and the Taga 'scores' and comments. Clearly both listeners heard significant improvements with the Tagas. They gave the HiRez Taga a score of 120%, and the HiRez Balanced Taga 125%. Now, the reviewer was perhaps a little cynical about the whole concept of mains conditioning, maybe because he had not heard particularly great results from some of our competitors, but a 20% or 25% improvement in the performance of any system is a huge jump in my opinion. Also the way the improvements were reported in the description of the units themselves – with 'for the first time it sounded good' expressions didn't quite seem to get carried forward in the discussion around the larger system (T+A PDP3000HC SACD player, T+A P3000HV pre-amplifier, ATC 100 Anniversary active speakers), and there may be two reasons for that with the 'big system' tests carried out....

At Quiescent we use two types of speakers, both passive. For a mid-price system representation we use a pair of moderately priced KEFs and they're great at what they do – they're fun and bouncy, give you a big-scale event and are pretty good tonally. For higher-end duties we use a pair of Avalons – not as punchy, quite, as the KEFs, but one thing for sure, they are mightily transparent. And I have to say, honestly for me, far more transparent than any of the active ATC speakers I have ever heard. The other factor with the review is that the reviewer clearly stated that the active speakers were not included in the tests, only the SACD player and pre-amp. Okay, it meant that the comparison of each conditioner was the same, but by feeding only the source and pre-amp, and leaving out, in effect, two mono-block power amps, then the VFM analysis in a typical bigger system is not representative. Only half the components were treated.

Our Taga distribution blocks are designed to treat a whole system, to bring the benefit of every component having less noise and microphony on it's supply. And in a high-end context, this is significant. I would expect, in a high-end system fed right through, to get at least another 5% improvement from each of the Tagas – so thats 25% from the HiRez Taga and 30% from the HiRez Balanced Taga. And probably even more with some really transparent speakers.

You can read the review here