Why does an audiophile grade power cord matter?


probably another beaten horse topic but I cannot find answers to quell my question.

Basically, most of us have homebuilder standard supply solid core copper wire with nylon, plastic or rubber sheathing that runs the length of our homes from some cheapo metal utility company supplied junction box to a 5 dollar leviton outlet Joe General Contractor buys at Home Depot. So the current at that 5 dollar outlet is what it is until we hook it up to our system.

So why does plugging in a 1.5 meter or what ever length of audiophile grade xxx hundred dollar power cord matter to go that last couple of feet to our components???
photonman
I hear the difference I just haven't heard an improvement. I had 2 pair of Quicksilver monos. One had the original power cord which was the equivalent of lamp cord and nonpolarized the other had an IEC socket installed with an "audiophile approved" power cord. Guess which amplifiers sounded better. The amplifiers with the original cord sounded better. I have also tried numerous after market power cords with varied results in several systems. If there is something wrong with the sound of your system and you need to smooth something over or brighten something up you might be able to do it with an after market power cord. I prefer finding the problem.
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Eliz....I've heard the same thing before...and to THESE ears, the right power cord makes the most positive difference.
Why do cables or NOS tubes matter? It's the same thing as in most of audio, it cannot be explained, only heard or not heard. I didn't buy the fact that a power cord could make a difference either, but listening has changed my opinions.
If you can't hear the difference, count your blessings and move on. :)