Sure I agree that copper is copper providing its true copper and not CCA, Copper Clad Aluminum. I would not use this stuff on long runs of 50-60 feet as the OP is doing. So when you go to your local Home Dept or Lowes, etc be careful as a lot of the brands of speaker wire they carry from mfrs like RCA, GE Pro, etc are actually CCA and not pure copper. Even though they say its copper.
I know the term OFC, oxygen free copper, gets a bad rap from some as being meaningless, but at least when you see this designation you know its pure copper. Good luck.
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