First, my question: does temperature affect performance of speaker cables, and if so, in what ways and to what degree?
My situation: I'm just now completing a whole new home audio system in my new home in Lake Tahoe, CA, where the elevation is 6,250 and the winters are quite cold and snow-filled. My speakers are set up on either side of a large rock fireplace that goes to the ceiling, and rather than having the cables exposed, I was thinking of running them down under the wood floors, in my crawl-space beneath the house. Now I haven't actually taken any temperature readings down there in the winter, but I do know that it's certainly a lot colder than above the floors. The only insulation from the outside is the cinder-block foundation walls. The crawl space is about 2-3 feet high.
The cables are Audioquest type 4, and the distance that they would be under the floor is about 6-8 feet.
Temperature will affect the dielectric insulation around the actual wire but there should be no noticeable difference in sound quality at those temperatures.