I was always quite sceptical about the use of these things, especially since audiophile grade pc's start at around a grand for units that get the best revfiews. So, I did a little reading, and found that oneac as well as powervar units are readily availible on ebay at a fraction of the cost, like 10 cents on the dollar, and perform quite well. I bought the cheapest one I could, maybe 25 bucks, and figured what the hell, and gave it a go. It kind of satu here in the condo for at least a wekk as I wasn't all that motivated to even plug it in to be honest. Well, I finally did so tonight and all I can say is wow. I had no clue how much electrical noise is present in a playback system until plugging this sucker in. The background immediately got blacker, and my amp is known for a black background, so I was honestly very shocked. The improveent was hit-you-in-the-face obvious too. The only concern I have is that I feel I lost an almmost inaudible, but since I am so used to it I could hear it, in the upper end of the spectrum. I have read that most pc's cause a problem or two but improve a bunch, is this kind of what they were talking about? Anyway, just thought i would share my thoughts. I am going to replace the receptacles, rewire ir, bypass a couple led's, and the unit is supposed to sound even better. I will report back. Best 25 bucks I have ever spent on the rig!