Frap, Floyd Toole has done more to determine what audio quality means than all of us here put together plus the fine fellows at all of the hi-fi magazines.
Sean, the "blind test in less than familiar surroundings" is a red herring. What do you think of blind tests in familiar surroundings, with the listener's own gear (most of it, except for whatever different is being tested)? Are those invalid, too? The fact remains that ABX testing still is the most accurate and sensitive means of detecting audible differences between audio devices.
Jaykaypur: What would you think of a guy who puts in a new $1,000 power cord and actually gains no improvement whatsoever, but merely thinks he gained 1 dB somewhere? Would he be better off as he is, or would he be better off more knowledgeable and $1,000 richer?
Bmpnyc: The quality of the copper will have an effect on the resistance of the wire. However, the difference in resistivity between "pure" copper and standard commodity-grade Cu is infinitesimally small. Lamp cord, if the overall resistance is small enough, can be as acoustically transparent as any "single crystal" or other hyped-up wire. Some people will give you all sorts of baseless technobabble about the quality of the insulation or the wire geometry. Yeah, right. The characteristics of wire can be boiled down to three electrical parameters: resistance, inductance, and capacitance. In speaker wire, because it's part of a low-impedance circuit, the resistance is the most important factor, so short and fat rules the day. The capacitance of even zip cord is so low that it doesn't begin to affect signals until you get up into hundreds of kiloHertz.
Bear, someone might hear a difference if they separated the lamp cord as you suggest, but would they hear a difference if they didn't know if the lamp cord was separated or not?
Abe, I'll answer your question. No, using power cords as tone controls is silly. For that matter, I think using interconnects as a tone control is silly, too.
