Stranded vs Solid Copper

You can use Wiremold, would look a lot neater IMO than EMT tubing. Use the starter box over the outlet, then run the channel housing the bare conductors along the wall on top of the floor moulding and up to a Wiremold surface box that holds the HG receptacle.

Thanks for the very good suggestion. Looks like they have a product to hide the vertical tv cables.
thanks

Not sure how the sound is affected between solid and stranded but the best thing for HIGH current is stranded because of the skin effect of AC voltage (it actually travels on the outer layer of wire). 

This is I know from being an industrial electrician. 

Myself Use Verastars excellent high purityCopper foil speaker cable,and Silvergold alloy foil interconnects . A flat foil has more surface area then  equal size awg guage wire.and very thin diaelectric. That may why it sounds very balanced . I have had several very good brands for me this is high enough 
in quality without breaking the bank.

Your decision on solid core is good. If you ever wanted to go stranded, Litz 9.5 awg from partsconnexion would also work great. You do need a soldering pot to prep the ends. Each individual wire has a coating. It must be removed.

If your going to build a box, do an internet search; X capacitors and Y capacitors. These little beauties remove hash from the power lines. Unless I'm mistaken, the X caps go from hot to ground, and neutral to ground. The Y caps go from hot to neutral. A world of difference almost forgotten in the diy world.