@tom1000
Good power cords can make a difference. However, there is another question that needs to be considered. Are you capable of hearing the difference?
Exactly!
This is the issue that so often goes unheeded in audiophile circles.
We can measure X-rays...but you can't perceive X-rays. We can measure portions of the electromagnetic spectrum far beyond human perception, we can measure sound frequencies far beyond what human's can perceive, and on and on. The fact that something is measurable by instruments DOES NOT automatically entail it will affect sound in a way audible to the human ear.
If you measure various wires, even different spools of the same wire, you can get slight deviations in the measurements. In of itself that DOES NOT entail we can hear those deviations.
That's a different question which is answered by controlled listening tests, to understand the capabilities of human perception. And given the problem that if you see something change you can think you hear a sonic change, it's best to control for that variable. This is why, for instance, in a standard hearing test you are blinded to any visual cue as whether a tone is being played - you have to go strictly on whether you can actually hear it. It's how they find dips in your hearing, or in tests for how high frequency you hear, you won't be given a visual cue that a tone is being played. Say the average middle aged audiophile came out of a controlled hearing test whose hearing leveled off at 14 khz. If that audiophile protested: "I don't care if your test says I can't hear over 14 khz - perception is subjective and I can tell you I CAN hear over 14 khz!"...there would be no reason whatsoever to take him seriously.
And yet, we get essentially this complaint over and over in the audiophile domain. Controlled listening tests are dismissed as if the idea doesn't even matter, and whatever you think you hear settles the matter.
That's FINE for anyone to take that route in buying whatever they want.But it's not good if you actually want to get to the truth of what is going on, nor is it a firm basis on which to make claims about the audibility of X or Y cable or wire.
It becomes like a form of faith in the audiophile world. Note that a common comment made against those who support or use blind testing is "it's too bad you feel you can't TRUST your hearing, as we do." So it's turned in to a sort of character fault, similar to the religious idea "if you require more rigorous evidence, that's a character fault showing you don't have FAITH."
There is a paradigm that can be unbridgeable between those who won't shake their faith in their inviolable perceptual abilities and those who recognize the reasons for controlling variables. Fortunately there is a spectrum of attitudes and not everyone is so intransigent and can consider the reasons for better test procedures.
The only way you can answer this question is with a hearing test and most people will not bother with finding out the truth about there hearing.
Yes, and if one is really pursuing the "truth" of the matter, it makes sense to be rigorous in that search, and not just ignore obvious variables of human bias that can be controlled for. Would you agree?
Also: The type of objective evidence that is most pertinent to cable manufacturer claims are those that are most conspicuously absent:The measurements showing that the AC cable affected the OUTPUT OF THE AUDIO SIGNAL, and in an audible way.
One can measure variations in the behavior of cables, but if the claim is this alters the signal at the audio output of a device THAT is where we'd want to see supporting measurements. But instead, all you get at that point is marketing, and anecdote.