comparison of different dedicated AC line types?

I've run 10 and 12 gauge both romex, Greenfield, and a several others such as THHN wire twisted and pulled through conduit in my eight dedicated outlets. One of my 10 gauge twisted THHN wires were even cryogenically treated in deep submersion.
To be honest I don't notice a difference in sound bassed upon what I described above.
I have tried a number of different high end audiophile outlets, and I do detect changes in sound with them.
I'd suggest you run whatever is the easiest for you that meets your code in your location.

if you won't find anyone done the exact comparison, you can do that on your own hiring electrician and requesting him to provide a couple of different dedicated lines that you're gong to be experimenting with. make sure that he doesn't take you as a nut case tho.

Thanks for your responses. I am capable of running the wiring myself as I was a mechanical contractor.
Thanks to Lak as you have done what I was interested in. I think I will run two different ones to see if I notice any difference in my setup, then go from there.

I would run 10GA to an amplifier.

It's an AC line. Nothing special is required. 12 GA should be fine unless you have very large amps. An AC power line is a noise source, so it is silly to shield it.
The whole point of an audio equipment power supply is to stabilize and clean the power to the electronics. If you have adequate current carrying capability, you are fine.