I use Signal Cable speaker cables for my Tyler Mini Rears for my surrounds & they sound just fine. I have one cable that's 25ft & another that's 35ft. These are copper cables. My mains and center speakers are are the full Linbrook System wired with Verastarr Silver Ref & Ultra Ref. The mains and center speaker wire is made with silver over copper and I don't have any evidence of an unbalanced sound or a bad match between the speakers. Everything seems ok given that they're only "surround speakers." I've considered getting the Verastarr Ultra Ref for the surround speakers but I can't justify the cost/benefit factor. The signal cables were about $200. I use a TGIII for my processor.