LFE/Subwoofer cable in wall?

I want to add two subwoofer wall outlets in the back of my audio room. 

What kind of cable should I use? A local higher end audio company said they use RG6. I was just wondering if this would be the best cable for that. Because it appears as soon as I ask for pricing the install of the LFE/Subwoofer cable to someone the price goes up but if I ask for two RG6 coax cables to be rain to the rear of the room, its not to bad at all. 
Assuming this is a balanced line:


If at all possible you should run a balanced line to minimize noise.  You might also want to save some money by connecting one subwoofer to the other instead of having 2 cables run.
So you’re saying run that balanced mic cable indoor the RG6, ok…then it will just need to have a RCA plug in the end?
Oh, yeah, so RG6 is not the appropriate cable for analog audio, so not sure why this was suggested.