The better the copper, the better the sound.

Triple C will sound better than OCC which in turn will sound better than OFC and so on. Of course cable geometry, construction, solid core or multistrand, plus materials used for insulation and sheath play a sifnificant role also.

If making your own plenty to choose from big Japanese brands, Furutech, Nanotech, Neotech, Acoustic Revive, Oyaide (not order of preference).

@petg60 Triple C is not inexpensive! Furutech Alpha OCC DUCC DSS-4.1 is c.$500 per meter off the spool. Any other sources?

@rbull11 I found the solid core version superior to stranded. 

Between solid and stranded...you might prefer the other in your system.

Hi OP,

In my family room I have runs of 35 and 25 feet.

so expensive speaker wires are not practical.

I made 4 individual cables using 10 gauge all copper Audtek wire from

parts express.  No silver for me!  I soldered on spade connections both ends.

ok I did use silver solder.

Great value for longer runs or any runs.  Any speaker benefits from bi wiring and eliminating jumpers.

Audtek 10 AWG OFC Speaker Wire 100 ft. 

Audtek Electronics Part #100-029    

Model: SKRL-10-100