Redbeard: The parts to make a "real" AC filter are all commonly available. One need not even buy parts as you can buy commercial grade units that will work phenomenally well. Just make sure that you have a freight truck to transport them, a dolly to wheel them in on, the physical room to mount them and an electrician to wire them into the system. Obviously, what i'm getting at is something that will "work right" is NOT a "lightweight toy".
The reason that most audio based manufacturers make cables and "audio grade" PLC's is that the profit margin is WAY, WAY high. This is not to mention that one can build, package and ship a "Super Duper AC Snake" for peanuts as compared to what it would cost for the chassis alone of the type of device that i'm talking about. If you were in business strictly for the money, what route would you take ???
As such, P.T. Barnum was right. Most of the people that he's refering to are audiophiles and they are investing in wires / cables rather than forcing the companies that build their active equipment to do it right. On top of that, when the "snake oil" wires, cables or PLC's don't live up to the hype, they disregard everything else in the same category. After such an experience, many folks will even "black-ball" products with real research and technology invested in them and remove the mass majority from their systems. Either that or they keep throwing good money after bad trying to find something that truly is "magical".
It's too bad that many folks that are truly seeking to upgrade their system end up resorting to buying such products based on industry hype rather than educating themselves and finding the "real deal". Sean
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