There has been a lot of technical study of hifi and cables. There are many links in this part of the forum to various papers studying various aspects of cables. Then there is all of the study that has been conducted by the big cable makes such as Belden through to the 'extensive R&D' claims of smaller audiophile cable makers. Then there is the Audio Engineering Society. Then there is all of the blind and ABX tests. Finally there are the hifi makers themselves and all of the bits of wire used inside hifi.
Hifi cables as a specific product began in the early 1970s (roughly). So that is 40 years worth of study. The result, nothing new. We are still using the likes of LR&C and skin effect which were first discovered in the 1800s.
So the evidence is weighted very strongly in favour of there is nothing inherant in a cable which affects sound quality. The same kind of weighting you would give to the sun rising again tomorrow. It might not happen, but it is highly unlikely.
