if you can, establish a relationship with a dealer who will agree to loan you cables for a weekend. put on those CDs/LPs you've listened to a million times and see if anything jumps out at you: are you hearing details you never heard before? is the bass better? is the overall tonal balance improved or just altered (some cables allegedly have a 'mid-bass bloat')? etc.
by the way, in the interest of full disclosure, I do think that going up from 'zip cord' cables can improve the sound.
by the way, in the interest of full disclosure, I do think that going up from 'zip cord' cables can improve the sound.