All very interesting!....especially as PVC dielectric is regarded as audiophile ''dog's doo doo''
I currently use 40 year old solid copper enameled winding wire of 15 gage(not twisted together). Two lengths per speaker (about 30 feet each run ) and have never heard better wire in my system - ever!
Don't know what they coated this stuff with back then,but you CAN NOT burn or melt it off with heat. You can only scrape it off with a scalpel.
So, I'm gonna try the 5 shotgunned PVC electrical cable. However, as in Australia, we have the 240v rated stuff, so I wonder if it would make any difference?