Need a good "under carpet" speaker cable

I can recommend some stuff that's like $15/ft, ultra high purrity 6/9's copper, sounds pheonominally good infact, but it's kind of an industry secret...so not sure I should spill the name
Audio quest makes some stuff however, that's at least 4/9's copper, wish sells for like $6/ft, and sounds pretty descent otherwise.
I would basically find the highest purity copper flat cable you can find, by checking manufacturers website otherwise, and contact someone about availability and price.
Good luck

I would look at the Nordost line of cables, they make excellent cables at all price points. Good luck.

I'll second the Nordost line of products. I use Blue
Heaven which is probably a bit expensive but they also
make cheaper cables.

John