Do I really need to Bi-Wire?

For what its worth, MIT bi-wire cables have a specific pair for high and low frequency connections. Check out the MIT Terminator 2 Bi-Wire. 1999 models cheap at AudioAdvisor.com

Here's an interesting phenomenon: WHich input do you have the cables going to? If the cable goes to the woofer posts, and the jumpers go to the tweeters, your highs will suffer. IF you go directly to the tweeters, you will get smoother highs, at the expense of bass response. I have heard that more damage is caused by going directly to the woofer, but I cant remember the science behind it, or exactly which thread (it was on audiogon) that I heard this in. I heard a difference in my system, however. I was using Audioquest SA-40 (silver, 15AWG) on my 805s. Wanting to get around the stock jumpers, I got some Audioquest CV-4 (copper, same geometry and gauge as the SA-40, however) and tried it both ways. I LOVE the Silver on top... the highs are great, with acceptible bass response. I felt that in my system, the silver cable was an all around better performer (identical cables, except for the metal) than copper. Mixing cables was definately cheaper, but if I could, I'd get another identical set of silver cables. Interestingly, I went back to the stock jumpers, and could definately immediately appreciate the (now missing) benefits of biwiring. I found the differences to be very noticeable.

I have found the improvements from biwiring to be substantial, even over an internally biwired configuration(ie + & - from amp going to 2 sets + & - to speaker). I am told that even with an amp with a good damping factor there is enough electrical energy traveling back from the woofer down the cable to the amp to interfere with the treble/midrange signal heading to the speaker from the amp. Whatever the case true biwiring made a very noticeable difference in my system. I would also keep the cables as similar as possible, identical if possible. I have heard several systems using the same cable except "silver on top" like Gthirteen and they sounded great. Don't mix brands or geometry however.

Thanks guys for the great advice. I think I'll take the plunge and get a second stereo pair for the 805s - I'll probably get the same pair as before just to be on the safe side.

Outlier, do these speaker cables have individually insulated copper conductors? I will presume they do not(too many conductors to insulate). And that is why I will recommend getting a pair of AudioQuest Indigo, Forest, Cobalt, or Midnight. Will cost you less than $200. Run them to your mid/HF binding post, and your current wire to the LF(not as critical of wire). I think you may be really surprised. The stranded wire can cause a lot of edginess, glare, haze, and shrillness. Perhaps, this may be the key to unlocking the true potential of your system. Good Luck!