This is one of the big 5 ongoing discussions:

1) The Cable Crusade
2) "Telltale" Sounds of Amp Circuits - More Than Just the Numbers Game?
3) Bi-Wiring - Cable Orgy or Sound Practice?
4) DACs - do they make a difference?
5) Tubes vs Solid State - Why They Sound Different

So you'll get a fracture down the middle on any of these topics - a debate will again rage, and will last for 3-6 days until someone asks a question on another of the big 5. One side will argue they've tried and heard it, the other will argue they've tried and not heard it or will post evidence why thanks to the laws of physics it couldn't be so.

Bren R.