Help with bi-amping


Can some of you help me to understand bi-amping?
I'm considering bi-amping my speakers, but I would like to know more about what's involved. Obviously, my speakers are bi-ampable, so my question is surrounding the amps. If I have 2 100w stereo amps, one for each speaker, does each speaker then get 200w of power, since I'm feeding one speaker with both channels? And what about the preamp/amp - does the amp have to be a "biampable" amp, or will any amplifier be capable of doing this, and does my preamp have to be biampable? Right now, my preamp only has 1 pair of front outputs - do I need 2 pairs? And lastly, do any of you have experience with both bi-amping and bi-wiring, and how do they compare, musically, logistically, financially, etc.
Thanks for any help with this topic.
ktsteamer
A 100 watt amp is still only a 100 watt amp. In biamping it becomes somewhat like multichannel amps and though the power of the amp is the same - each amp works less than it would to handle all of the speakers in the load that it is presented.
I tried vertical bi-amping, by borrowing a VT-200 to match with my VT-100. It didn't fare that well. I suspect it was due to the lack of an active crossover to balance the signals. Who makes good crossovers? Has anyone done a real comparison? That is not 2 amps against your old amp but 2 amps against one amp which is the equivalent of the 2. Have you compared 2 100 watt amps against a similar 200 watt model?
"Who makes the best crossover" ... In my opinion it is Krell. Their KBX can cut frequencies like a knife and can be customized by Krell for any speaker. But it is pricy.
A good quality crossover is the Bryston 10 - it retails in the 1400-1600 range. The Krell is better but a lot more - see if you can borrow a Rane crossover 300-550 from a local music store or rent it if a high end dealer will not loan you an active one. It can at least give you an idea of what an active crossover of a higher quality can do for you as far as control and frequency separation are concerned.
I disagree that using two 100 watt amps or two channels of a 100 watt ampis the same as a 100 watt amp. As evidence, often times one will see that an amp can be bridged to provide (at least) double the power of the two channel mode.