I would give Signal Cable or Blue Jeans Cable products a try, and then later try some more expensive stuff if you want to.
I'd try copper only first with the great equipment you've assembled. Give them plenty of time to settle in and give yourself time to discover how much information is there, copper's richness and detail aren't in your face, so be patient and listen the detail is there. It took me time to go from silver to copper but now I don't see myself going back. I don't think you can go wrong with Cardas or Kimber if you want to move up in the line or out of the line both are resellable at a minimal of loss.
If you want best bang for the buck, try PNF Audio. it will impart the least sonic signature of its own on your system and will do what a cable should, cleanly transfer a signal. The PNF Symphony speaker cables and ICON ic's together can't be beat unless you spend orders of magnitude more, and even then I'm not convinced you'll get truly better performance.
Thanks for all the responses. I initially considered getting something from Blue Jean Cable since they seem to be a quality cable for the money. But then I thought that since I already invested quite a bit of money in amps and speakers I might as well getting some of good quality to get as much as I can out of the system, which is why I came on this forum to ask around.
Thanks again, I will look into those suggestions.
In addition to Signal Cable or Blue Jeans Cable you may consider Canare Star Quad 4S11 available as DIY or assembled from haveinc.com. These are all good cables that give a more neutral signature.
Many of those "expensive" cables are more apt to give their own sonic signature.
p.s. very nice system you have going - congrats!
Congrats, you have some great gear.
Crimson is a little heard of English company with only one or two US distributers, but the cable is first class. They'll blow you away... Turned my Special 25's into a whole new speaker. Great speed, very detailed top to bottom, they sound great with tube gear... Use them throughout. They need to break in for about 50 hours but OMG.
I auditioned Red Dawn on Graaf GM200 and EAR and it's a great match. Found NOT a good match on both Pass and Krell. Better match with Tube components.
Check out Zu Varial MK3 interconnects. It works especially well with tube components. Varials replaced most of my very expensive cables. Check out the 6moon review.