Generally Speaking

Okay, stick with me because no matter how many times I rewrite this it still sounds stupid. Lets say I'm looking at "Company X" and they offer four different speaker cables, lets call them A, B, C, and D (A being the best). "A" cost 1500.00, and "B" costs 800.00. Generally speaking is it better to go with "A" or have "B" bi-wired with the result that both sets now cost 1500.00? I know something like this must have been posted before, but 1) I can't find it, and 2)this might give new members a chance to post(no one likes posting on a dead thread). Thank you all in advance.
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Vandersteen Audio states that moderately priced bi-wired speaker cables will easily out-perform a single run of more expensive cable. Of course this is with Vandersteen speakers that have been specifically designed to be used bi-wired.

I personally believe that cables in the middle of a companies line to be probably the "best value" wires, ie they provide 90-95% of the sonic quality of the company's most expensive stuff. Cheers. Craig
Garfish and I are in general agreement on this topic, although my own experience is that the "knee" in the incremental improvement curve may be lower than the #2 cable in a company's product line. As with nearly all high-end audio, you pay more -- typically a LOT more -- to gain that last bit of improvement.
your presumptive formula does not apply to a number of cable companies' price lists; i.e., some class "b" bi-wire sets cost more than twice the price of a single run of class "a." that being said, my speakers of choice, avalon, have migrated from tri-wireable to single-post terminations, based upon their findings (and mine) that there is NO improvement from single to muti-cable terminations if your speakers, including most importantly xovers, are well designed and implemented. -cfb
I would go with single run of your "A" cable!
My answer would depend on the speakers in use. If the speakers were TRULY isolated between the low and mid / hi frequency drivers when you pulled the jumpers, i would opt for "good" quality individual / seperate runs to each set of binding posts. If the drivers were still electrically connected internally after removing the jumpers, i would opt for a more expensive single run with good jumpers.

There is NO benefit to "bi-wiring" when you keep both signals in the same cable and simply split or share the cable. If you MUST split the cable or already have a pair like this, i would leave a good quality jumper intact for the lowest possible resistance between the two positive and two negative terminals. I know that this "voids" the idea behind "bi-wiring", but that is what i see as working best from an electrical standpoint. Sean
I have run many different cables and I have found a benefit to biwiring with my current speakers. I compared a biwired pair of cables to the same brand but better model single run cables with jumpers and the biwire sounded better.

I cant explain it and Im sure that speaker design has something to do with it. I know that my speakers have an odd crossover design that makes them ineffecient. (I think it doesnt use compacitors in the crossover) Perhaps that has something to do with it.

I have heard the technical argument and I agree in theory it sounds as if their shouldnt be a benifit but I also know what I heard.

Cornfedboy has a point in pricing. The lower model biwire retailed for $300 more then the better model single run.

Have the best of both worlds, buy the cables used and get 2 runs of cable 'A'. That one was not too hard to figure out, lol. I think it would be speaker dependent, i.e. if speakers x-over networks are there storng point or not. I personally use a shot-gun(external) biwire set up, and found that I have much better bass with this set up.
If I remember correctly the reason I was told bi-wire sounds better is that when the drivers travel in the oppositte direction that they send a little interference back into the other driver. The extra length helps dissipates this interference. I cant swear by this but it was what I was told.
TRUE bi-wiring ( individual cable runs to the high and low frequency drivers ) can contribute the following benefits to the system IF the drivers are actually isolated when you pull the jumpers:

Increased control of the individual drivers due to lower series resistance

Less crosstalk / intermodulation distortion between the woofer and mid / tweeter

Increased bandwidth / more linear response due to optimized cables for each frequency range

There may be other benefits to doing such that are inter-related to the above. You might also be able to achieve a portion of the above by using an all in one "bi-wire" cable IF the cable uses individually insulated conductors. For best results though, you really do need individual cables for each frequency range. Sean