I was a touch sceptical about mains filtering, sure I've got the exceptional interconnects, the energy absorption hi-fi stands, the spikes, the sorbothane and granite and they all work superbly in tightening the sound. But the mains? Fairly constant and surely it can't affect the sound right?
I popped this in front of my system (Musical Fidelity A3.5 & Tri-Vista DAC 21, Audiolab 8000Q & 2 8000P's, Martin Logan Aeon-i electrostats and MJ Acoustics PRO100 sub all hooked up with Krystal Avenger interconnects and QED X-Tube400 speaker cable) and the result was delightful.
For the ludicrously low price this has to be worth having. Whether you are an audiophile like me or just have a decent hi-fi, for the money this is a superb purchase. The effect on the sound was an overall tightening of the image, vocals became crisper and very realistic and the detail was brought out even further than it had been.
I'm now considering spending a lot more on a mains filter if this is the result of spending £40. Superb.