while I'm not here to make any claims on power cords but even Keith's post has lead to a alcoholics article on power cords . & the reason I have gone to a DIY route ( I also am putting in dedicated power circuits that will be breaker box to wall outlet no splits/splices in the 10 Gauge 3 wire romex ) note that the writer of this article is from Australia a direct quote here on US A/C power
( " One useful observation is that the mains in the US seems to be basically pretty nasty, and not at all what we are used to in Australia . Interference seems to be a major problem, and if this is the case, it will find its way through the power supply and into the amplifier (or other equipment) if the power supply is not well designed.Also, because of the lower mains voltage in the US (nominally 120V), the current drawn by power amplifiers in particular can cause real problems with cheap light duty cables. I have already made this point, but it is worth making again. Use of a heavy duty lead (possibly shielded if interference is a problem) will make a difference. Whether the power difference is audible or not is debatable, but elimination (or even reduction) of mains borne interference is likely to result in a worthwhile improvement in sound quality." )
he goes on to say that the US plugs on P/C's are some what inferior to most of the UK,EU & AU as well the wall outlets being inferior .
here's the the whole article page # 6 that deals with power cordshttp://www.audioholics.com/education...-cables-page-6
****now a disclaimer : I'm not drinking the Koolaid or buying the snake oil on speaker wires & interconnects that he talks about on these items ,in this same article...
good old 12 gauge zip wire works for me as well as Monowire interconnects****
But as he states the US has a really nasty power grid.
the power that comes into US homes varies wildly by region,state,town, even city blocks to even how your house/apartment bldg/condo was built . Even in your own home a Personal computer, refrigerator,light dimmer ,numerous various electrical items add signal noise back into your homes A/C power . In my house I do notice that when a vacuum is on the FM signal gets fuzzy ,the lights slightly dim at times when the refer motor turns on ,the whole house lights dim when I use power saws in the garage.
I'm making my own Power Cords in a some what larger gauge than a stock power cords supplied equipment with US standards with upgraded plugs & outlets . It's a personal choice based on my own experience with the above issues .
I am also using a power conditioner that uses a large toroidal power supply to clean up & stabilize the A/C current to a constant 120 volts . I do not advocate anyone to buy a power cord that costs more than what the upgraded DIY parts cost .
Soo plz no hijacking or flames ,this not the thread to debate cables & wires. If you don't have the issues that I have, as noted above, then you do not need a power cord .