I see a lot mentioned about bi-wiring. I am not familar with this. I know you must have speakers that can be bi-wired and they are configured for bi-wire by removing a buss bar to seperate speakers and/or crossovers within the cabinet. I have also read that you need to have an amp that has bi-wire capability (two left and two right speakers outputs - and not to be confused with speakers A & B).

Can someone explain what takes place within each speaker when it is set up for bi-wiring? What are the advantages and disadvantages if any? What if my amp only has one set of left and right speakers outputs (but has something called loops for additional amps), Can you accomplish bi-wiring if you had two amps? If so how would it work?
All your questions will be answered at this website which
includes diagrams for bi-wiring.
Also your speakers owners manual should have some info on bi-wire set-up if you have bi-wire speakers. Remember to remove connecting bars between two pairs of cable connectors
if you bi-wire.
Sfrounds: Biwring is very simple. At some point, the signal from your amp has to be split in order to feed the individual drivers in your speakers. Normally, this split occurs at the speaker terminals. With biwring, the split occurs at the amplifier terminals. Does it matter where this split occurs? Electrically, no. The full signal passes through both wires, and exactly the same signal reaches the low- and high-pass filters feeding your woofer and tweeter, respectively. Assuming you're using the same cable for both runs, any distortion introduced by the cable will be identical to the single-wire alternative.

In other words, biwiring makes no difference. However, many people report that they hear a difference when they biwire. There are two possible explanations for this. One is that listeners tend to be swayed by the power of suggestion. The other is that there is some mystical, magical force that no one's ever been able to identify, but some day a new Galileo will come along and tell us what it is.

There is one advantage to biwiring, however. If you're the type of audiophile who actively seeks out cables that color the sound, then biwiring gives you twice as many opportunities to do so.
Jostler3 may be partially right, but he's not completely right. His theory only makes sense if the connection between the bass and treble speaker connections are connected by jumpers made of the same cable as your speaker wire, and your wire and jumpers happen to have the same properties as the binding posts themselves.

Many bi-wire ready speakers have their bass/treble connections bridged by posts. I had a pair of Mission 753 speakers with gold posts connecting the low and high speaker terminals. Those rods were not a good connection. The treble was favored when the speaker wire was run to the high connection, and the bass was favored if it was run to the low connection. The resistance through the connector & crossover was obviously different from the resistance thru the connector post. Bi-wire cable sounded better than the gold posts (treble and bass were balanced).

I'm not saying that bi-wiring sounds any better or different than wire jumpers (I didn't compare), but it was better than the manufacturer supplied posts.

A dealer told me that our choice of bi-wire or wire jumpers should depend on our speakers' cross-over design (and he wasn't trying to upsell me...the cost was the same, and I wasn't buying anything). I'm not a speaker designer...I don't know if that's true, or not.
Phild: I have a hard time believing that a one-inch gold(plated) post would have an audible effect, unless the connection itself were a problem. But that's what makes me a skeptic. Even so, buying another 20 feet of cable seems an extreme solution. Replacing the posts with a short bit of whatever wire you're using should suffice.

With all due respect to your dealer, the crossover gets the same signal, wherever the split occurs (again, assuming you're using the same wires, and all the connections are sound). He may not have been trying to sell you something. He may have been repeating what he was told by a manufacturer's rep who was trying to sell HIM something.