best speaker wire for extra long runs


I have a 45 foot disctance between system and speakers. Currently I use whatever the thickest gauge Monster speaker wire is - I forget the specs. Is there an upgrade option that will not break the bank that would be a really significant upgrade from the Monster for such a long distance? The only option I have seen is from Cardas, but I do not have a sense of whether that would provide a significant step up in sound quality from the Monster. Speakers are Sonus Faber Grand Piano.
gipp
Thats a lot of speaker cable. Does your pre and amp have XLR outputs and inputs? If possible, relocating your amp closer to the speakers and running balanced between amp and pre may be a better option. Mogami XLR mic cables are quite reasonable.
For various reasons, 45 feet is about as close as I can get, but I do run balanced connections between amp and pre-amp. Now, I'm just trying to make the best out of a bad situation.
The Cardas Neutral is the best choice I know of. Occasionally a friend of mine has access to used CArdas cables and once in a while, a long set show up. Jallen
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With respect to Eric and Mrderrick, I think the OP made it clear he can't relocate his amp.

I'm no speaker cable expert, but I believe that over such a long run, resistance is your biggest enemy. Using the heavy gauge Monster is a good idea, but it may even be worth thinking laterally and investigating stores that sell equipment for PA and concert gear. Speaker cables at live shows often have to run over 100 feet and still maintain quality (audiophile quality I don't know); you may find they sell quality copper in heavier gauge than any hifi store might stock.

Just a thought...