Power Cables and Wall Sockets

I think all 15 and 20 amp outlets in a home are now required to be tamper-resistant. The Hubbell heavy use hospital grade outlet listed above (HBL8300GY) is not according to the specification. For tamper-resistant ones, look for HBL8300SGxx.

When do we get threads about putting heavier OCC wiring in each component (as applicable) or speakers? 

audioquest overcharges for their wire they're buying it from neotech in Taiwan which makes some of the best OCC single crystal wire which is the best wire for audio so you can look at companies like Harmonic technology acoustic Zen zenwave they all use OCC single Crystal and are a lot cheaper than audioquest which over charges like crazy.

@imaninatural 

"Without knowing for certain, it seems to me that power cables can only be as good as the in-home wiring coming to the wall socket. "

That's the logical conclusion.

@ghdprentice 

Like many others you say the last six feet of passive cable can make a big difference.  How?  Why is the last six feet different from the five miles or whatever of cable from the power station to your home and all the transformers, joints etc etc on the way?  Please explain in terms of physics how a passive cable can do this, absent active components and power conditioners that certainly can affect the quality of the power we receive.

One thing that I am curious about is if upgraded power cables will eliminate the issue of my lights dimming when listening at reasonable high volume.

If the lights are on the same circuit as the amp, then probably yes.
If not, then you likely have something like a 40A service coming into an old house.

They have volt meters that plug into a socket, just plug it in somewhere else see what the voltage goes to when the amps kick.