Shielded Speaker Wire 12AWG

@cgbgreg 

I agree with others - there is no need to use shielded speaker cables.

Firstly, they carry huge signals compared with interconnects of phono cables, so any RFI will be miniscule in effect.

Secondly, because a speaker cable is a pair of wire bundles, what  affects one bundle pretty much affects the other in the opposite way - this cancellation effect is crucial for very high speed cables like ethernet, which mainly uses unshielded twisted pairs these days.

Thirdly, adding a shield will increase the capacitance of the cable, almost always for the worst.

Speaker cables may benefit from being gently twisted but most often the two conductors will also be separated by about an inch.

Similar arguments apply to balanced interconnects.  Balance is good because it increases the signal to noise ratio.  Shielding is debatable.

If cables must cross other cables, try to do this at right angles to minimise interference.

I'd caution you about centre speakers, but it is off-subject!  Nevertheless, have a good look at this Discover the Surprising Flaw in Center Channel Speakers

I appreciate all the great guidance and the video about center channel speakers. I am leaning towards the  T-14 Speaker Cable - DH Labs Silver Sonic https://share.google/Wo4rwTXnxtRYcwcu0

Hello cgbgregg, You can also consider Iconoclast spkr cables. Due to room layout, I have 25' runs of Iconoclast TPC. Immediately upon listening to them, my boss who is always concerned about my audio expenses, smiled enthusiastically (!). The design inherently rejects noise, but the point is that even w my long run, they sound clear, revealing, enlarged soundstage, no noise. If your length is more reasonable than mine, they will send you a pair with a 30+ day return. Bob Howard at Iconoclast was very knowledgeable and thoughtful (850-860-0940). I did a ton of research before ordering; No way I am returning mine.   

Blue Jeans Cable sells Belden 10AWG stranded cable. That's what I use.

Vh audio has cryoed wire

And analysis plushas very good awg wire 

 Shielded is not as important

I have  a 4 wire setup a common ground 

And a insulated isolated ground on its own buzz bar to the outside 

Everyday is the same No noise no sharing ground with other appliances 

My Audiophile friend electrician taught me this and breakers are silver over copper 

From Germany this ovoids the copper from oxydizing