Do I need 10 gauge power cord if I have 10 gauge from panel?

@jumia    No, I said there is no reason to match.  As long as your wires are big enough to comfortably carry the current being drawn.  It's that simple.

@jumia

I’m with @ghdprentice on this one:

"Only when comparing to other cords. This is not a pursuit with absolutes… maybe the desire, but we live in a world of imperfection."

As with many audio pursuits, experimentation is the key to success. Hopefully, you can get your hands on some good examples of premium PCs and give them a listen.

IMO, adding hospital grade plugs will have a larger sonic impact. I have 2 dedicated 20A lines for my stereo. It turns out that with everything running and playing music, 2 amps, preamp, phono-pre, dac, cdplayer, turntable, draws only 2.4 Amps. So, the 20 Amp circuits were unnecessary. 

@jumia 

What speakers are you driving with the commercial series Crown amps? As per their own recommendations, they were designed to be used in music halls and live performance studios, not for a homes living room. Also these were supplied with a 30A plug on a 10AWG  cable, to meet the commercial requirements of that amp.

This whole thing isn't making sense to me.