Cables -- Yes there are pretty significant changes in the sound of silver and copper. The choice is yours to pick the one you like. I own a set of Audio Truth Diamond and also a set of MIT xxxxx Pro-line reference. As in one of the responses above, the MIT far out performs the Diamond in every aspect of the music (as it should for 4x cost). I like some of the characteristics of both copper and silver, so my choice was to have silver from source to pre-amp and copper between pre-amp and amp. Main point -- audition cable additions for at least a week or two, have audiophile friends over to listen with you, and make your choice based on YOUR ears. Cables can make differences to the magnitude of a component upgrade of many $$. Other Toys -- I have had the opportunity to audition a great many "tweek" products... Some of them worked for me, others did not. They were again all tested with ears and an elixer of fine ale. The ones that stayed in my home are: Bedini Dual Beam Ultraclarifier, Marigo CD Cleaner and Cross Bow, and Audio Quest Ultra Connect. The others I auditioned either did not work or presented a trade-off in another area. Again, listen carefully -- even the tweeks mentioned above (except for the AQ Ultra Connect) do not always produce desireable results on all media. My 2 cents...
"Feng Shui" and "Floobie Dust"
These titles were once used in an edition of Stereophile reporting on some miscellaneous items from a CES show. Do things like Shun Mook disks, Shakti stones, silver vs. copper wire (the resistivity of silver is only a little greater, so is it the grain structure?), power conditioners (for example, there was a fairly interesting article in the current issue of The Absolute Sound debunking most power conditioners and filters), etc., make a difference? Is there any physical basis (in terms of an understanding of the physics) for the claims made by the manufacturers?