How can power cords make a difference?


I have read many threads about how "wonderful" this or that power cord made my system sound. For the life of me, how in the world can a 3 ft power cord make an improvement? Each manufacturer supplys a power cord.I can't imagine them puting something on thier unit that would not meet thier needs. After all, the power comes from the utility company into your house, you run a dedicated line to your equipment, you put a line conditioner/surge protector between your equipment and now you have clean consistant power then magically you have great music. What can 3 feet of $200 0r more power cord make a differance? Sounds like expensive VODO! Am I missing something?
edkoz
Thank GOD there are others out there in the audio world that believe that voodoo belongs in another demension other than power cords!!!!
Now you see, THAT's the problem. If you're going to thank God, you have to side with the believers. You must choose science or religion in this matter. Sorry, but there are no other paths to enlightened electricity.
It's all voodoo--cords, amps, speakers, all of it. Caveat Emptor! Run, kids, run!
In fact, if you ever see this little guy appear during a listening session, you'll know you've been gouged by the power cord voodoo devil!
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Changing a power cord could make a difference. It simply means that either

1) the audio equipment is too sensitive to the input power supplied

or

2) the electrical supply is falling outside the acceptable range for the audio equipment.

Good audio engineering design requires that equipment be designed to work properly and robustly under a range of power conditions. This is necessary because not everyone's home wiring is the same, nor is each home at the same position on the same electrical grid. Also the quality of electric power will vary with demand particularly at peak load times of the day (for example at mornings when everybody puts the kettle/coffee maker on, or on a very hot day due to air conditioning).

The solution to this problem is not to try different power cords but to find out which of the above 1) or 2) is the root cause of the problem and try to fix that. If necessary change house wiring, get a power conditioner or change the overly sensitive audio component.