Are upgraded power cables really worth the money?


My system consists of musical fidelity a5 integraded and cd player, b&w 703 and a rel 305 sub. I'm Im using purist audio musaeus interconects and speaker cables. I understand and can certainly see how these cables have helped my system, but am a bit aprehensive about investing in upgraded mains cables. Do they really make much difference? With the system I have what would be the right amount to spend on them. Any suggestions?
zeekzaak
tvad your advice sounds like my best bet. What would be an easily resalable cord to start with at a reasonable price?
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Does anyone have experience with upgrading/altering the installation hardwire between the fusebox and the wall outlet? Apart from installing dedicated lines, I could consider higher quality of the wires themselves ...
In theory I geuss the power supply in the equipment can only see maybe 5 feet. If you have a upgraded power cord and or a conditioner that doesn't detract from the music, this is all you need, and dedicated lines. You can upgrade wire but its not really going to help. Use 10 gauge wire for you dedicated lines of 20 amps instead of 12. This will ensure less power loss accross the run.

beerdraft
I am amazed no one has mentioned upgrading your electrical circuitry as the biggest bang for buck improvement in this area. I spent a few hundred dollars and added 3 dedicated audio circuits to my main listening room. I think that is by far the most cost effective change you can make, and the one an audiophile should consider first. For about half the cost of a mid priced fancy cable, you can make a permanent change that will likely dwarf what any one cable can do for your system.
I have always considered Audiogon members a great source of information and inspiration - I guess this is a chance to "give back" to the community. BTW, all of these changes and improvements are so dependent on individual rooms, equipment, wiring, etc., so you still need to match the advice to your particular situation - there really are no absolutes.