Which is better longer xlr or speaker cable


I have just purchased my first mono amps (Nuforce Reference 9V2SE's) giving me some new cable options. Currently I run a one meter pair of XLR and then four 5 meter pairs, as I biwire, of speaker cable. With the mono's now I can also do a 5 meter xlr and short speaker cables.

Which should produce better sound. And for equal sound quality, which should be less expensive. Any recommendations for a reasonable cost way to do this? I would like to get in new or used for under $500 for whatever additional stuff I have to buy. In option one I will need new speaker cable, in option two, new IC xlr. Is it OK to have different lengths of cable, probably 3 meters to the closer speaker?
Thanks
128x128gammajo
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Bettercables.com is also a great resource for reasonably priced longer balanced cables.
The $15 fifteen foot Hosa's are well made with silver contact Neutriks. When I had them I always felt shortchanged somehow. Now using long Kimber XLR PBJs with no urge to change them. Wire characteristics are typically described by the linear foot or metre so I'm inclined to believe the shorter the speaker cables the less relevant their quality. You've got a nice system and if you van get the new blocks close enough to the speaks now's your chance cheap out.
Guys - thnx for clarifying my point - no one here is recommending unobtanium XLR cables - I am not hearing you have to have ___ or you will die.

Rodman - your comment puzzles me a bit. Do you think that the microphone line from the lead singer or the featured soloist does not carry complex musical information? Aren't those the very things that we are looking to hear as they come out of blackness to enter the room surrounded by air precisely placed blah blah blah?

Music reproduction is a long and complex chain. But it all starts with a quality input signal (source). If its good enough to carry an artist to the mixing console its probably good enough to carry the mix to the speakers...

Mogami is good.
What you are sending to the amps is a signal composed of, not just one voice(vocal or instrument), but a compilation of everything and everyone performing, plus the imaging and ambient info contained on the recording, etc. A bit more complex than what is fed through one pro mic/instrument cable to the snake and console to be mixed. Do what you like. I've only been in the live music and home audio game for over 30 years. What do I know?