Should All Power Cables be Alike?

That  Furutech GTD-D NCF(R) is $280.00 a pop. I assume there wouldn't be a problem connecting that to the 20 AMP AC wire in the wall? Sorry, everyone; I don't know much about the electricians world.

Yeah, those furutech outlets are pricey! If you're going top of the line everywhere else, they're probably worth it. Otherwise, there are less expensive options that provide reasonable performance. I use Hubbell commercial outlets with non ferrous grounding straps. They were $10/outlet. 

So, regarding wiring.. 10 gauge can support 40 amps. If you have a 20 amp in the wall, it's probably 12awg if you didn't specify using a fatter wire. 12awg is rated to 20amp. 

But for power cables for high current items, like power boxes and amps, going as fat as reasonably possible often improves the performance of the amps. But, again, that's often just for high wattage amps. 10 gauge is as fat as is reasonable, usually. 

But then there are things like cable architecture and materials to take into account. It never ends!

This has been very helpful. I'm certain they put 12awg in the wall. I have 20amp circuit breakers. The manufacturer's owner manual for my power amp indicates that the AC should be connected directly to the wall outlet; not passing through my PS Audio P10. Is that the optimal sound quality approach?

Many members find that to be the case. I hate to keep saying this, but the only way to be sure is to try. I personally have not tried going directly into the wall, but that's because I don't have enough outlets at the wall because I have monoblocks. I plan on installing a dedicated line (right now there are 3 other outlets around the room on the same branch) and another outlet where it comes into the room. Then I'll be trying and deciding for myself as well.
What amp do you have?

So, you recommend using a 10 or 12 gauge AC power cord - I assume that translates into a 20 AMP AC cord from the AC wall outlet to the power center? I have 20 AMP AC wire to my circuit breaker.

The circuit breaker and dedicated line are rated 20 amps. Your PS Audio is 15 amps, so the wall receptacle would be a grounded 15 amp type. A 20 amp receptacle has different connectors.