Audiophile Receptacle question

I have a listening room and installed #-12 gauge 3 wire-that is 1-white 1-black -1-red and 1-naked ground 
reason is the wire is twisted-not parallel. That helps to fight radio frequency!

These look pretty good for a decent price. 

http://anticables.com/power-cords#!/Level-2-Performance-Series-Power-Cords/p/14644826/category=34611...

I'm with GS. I just did what you are proposing - and HG all the way. Put your money into Quietrock 545, which will soak up lots of $$$ real fast.

And no, I would not consider a vintage tube guitar amp to be high end audiophile. Not audiophile at all. Emphasis was different (POWER), and distortion tended to be high. But still should benefit from HG.

I'm a GC and I've been kicking around the idea of building a sound room above the garage. I don't know anything about room treatments (yet) or what receptacles to choose but, if you have room in your main panel or sub-panel, I would have the electrician set a separate 15 amp breaker for your lights and, a dedicated 15 or 20 amp breaker for your hi fi receptacles only (I assume your garage has existing receptacles for general use?). Ask for a double-gang box termination (4 receptacles). You can use 12/3 or 14/3 Romex. The braided 4-wire is for 220v ranges & dryers. It's braided because if it were solid you couldn't pull it through studs and joists. Canceling EMI wasn't really a consideration although it may work. Just a big cost for a "maybe" IMO. You can pull your ethernet cable to the next stud bay over from the receptacles in case you ever want a hardwired streamer. I would also put a 1 inch conduit from the top plate to the receptacle height just in case you want to bring another wire in in the future. Just my 2 cents