Matjet, All I'm suggesting ( and it only an idea that came to me recently....could be a terrible idea!)
is to place a mic in front of a real high end full range system and record with a suitable digital recorder a number of music tracks with the whole system wired up with ...say a loom of the 'pro' grade cables ...the type that the cable skeptics say are more than good enough (Belden for example.)
Then without changing anything,,mic position volume settings etc, replace all cables with say a real high end loom, something like Nordost Odin for example.
Then record same tracks. Then burn onto a cd, so track 1 is with beldens followed immediately with track 1 with Odins .
Then you can sit back in comfort and listen to the cd without worrying about all the things cable skeptics say will influence you're hearing.... Blood pressure changes due to changing the cables!. Time delay due to changing cables etc , etc.
and hopefully be able to form an opinion as to wether you can hear a difference and if it's an improvement and worthwhile or not.
Is only an idea but surly worth a try by somebody?