What do $2500 speaker cables sound like?

They sound like money flying out the window...

$2500.00 cables emit no sound by themselves :). But when connecting high quality amplification to good speakers, the sound should be more transparent, in some cases dramatically so. You should be able to pick up little details in the music that were muddy or not even detectable with the old cables.

There is a great debate over cables. I do not need to be a "believer" in cables because upgrading cables has produced objective proof for me.

I agree—They sound like money flying out the window 

Maybe i just use telephone wires.

soooo many brands. Cant be with all of them, my cable love is limited.

2500 dollar cables are a revelation in the right system but on most systems you will not hear much of a difference but when you have good enough equipment and speakers the difference can be quite amazing and stays that way.