All speaker cables are not the same. Let me make that clear before either camp launches an attack. Many are just fine. Some are bad. Some like bad. Some do not.
Many exotic cables do sound fine. As good as zip cord actually. Let me clarify that: Decent copper 14 or 12 gauge. I prefer twisted pair as I once had very long runs pick up an illegal 1000W CB radio. I see a lot of Amazon level speaker cable for sale that is copper plated aluminum. You can always go up a gauge or two to keep your DF. In really long runs, It is possible that the reactive parameters of different geometry can have some small linear distortion effect. If you run 50 foot cables maybe. Easy to measure. Long term, some insulation (vinyl mostly) is acidic and will corrode the cable. Audible? Don't know but green slime oozing out of the end does not make me feel good. At RF where the skin effect is relevant, it is probably very bad. ( slime is a combination of the plasticizer oils and the oxide). Poor termination can also cause an audible problem but another area right from the snake oil pit with very expensive solutions to 50 cent problems.
Unfortunately many do sound different in that they distort more to some degree. Yes, there are numerous OBJECTIVE measurements that identify these distortions, linear and non-linear. You may like these distortions, so then the cable is right for you.
The more you pay, the more your brain is going to tell you they have released some magic detail that was never in the recording to start with. Our brains are marvelous processors able to stroke our egos to the Nth degree. Do you hear a difference? Yes, you probably do, but it is not the cable unless your previous cable was some exotic junk. So enjoy whatever your brain tells you as it is music to your ears that counts. Reproducing music is more about fooling our brain than technical performance.
A topology I would like to see further investigated is inclusion of the amplifier output filters all the way to the speaker terminals in the feedback loop. That would eliminate any of this cable nonsense. Unfortunately, phase shift makes this very very difficult. Only slightly easier in a powered speaker as you have control. An interview with Bruno Putzes gave a hint that active filtering in the feedback can do this. I would love to see an ASE paper on it. Four wire sensing and a fixed known cable would be absolutely necessary. Nothing that is not SOP in the lab.
This viewpoint is based on the science as we know it in this universe. Physics and psychoacoustic. If you have any repeatable, demonstrable evidence to prove the contrary, I am all eyes and ears. Not " I think it sounds" which will not sway the objectivists any more than someone with an Ohm meter will sway someone who spent $1000 on some magic cable. Religion is not science. People are funny, that's all there is to it. Blind A/B testing needs to meet the same 6 sigma as is acceptable in any other scientific measure. It has never met that mark I am aware of.
