What do $2500 speaker cables sound like?

It depends on many factors including the source and amplification quality going through the speaker cables and the speakers themselves.

I noticed a significant change using Kimber Kables over Blue Jean Cables with my current system and prior to the testing and audition of different cables I was happy with the sound.

So I'd suggest to you its about the 'system' versus just the cables.

@raysmtb1  You may be right and if that's what happening I'm ok with it as I enjoy listening to music and my system as much or more than I did when I was younger.