I was a firm believer that cables do not make a difference, until recently I discovered otherwise and it just blows my mind. I have upgraded to tube amp, Focal speakers, Mcintosh DAC/preamp so tried new cables.
Having said that I'd still not pay few hundred or $1k for cables, dinising returns principle.
Was using AQ King Cobra, tried those, AQ Mcenzie, Better cables, and some other in the $300 or so range. The WireWorld Equinox 7, $200 for 1m pair sounded by far the best in my system. Very audible differences in almost A/B comparison (swapped cables in less than 1 minute, played same tracks again.)
I will try the Eclipse 7 at $400 as I am told it is a significant step, but that would be as far as I go.
Good luck.