Yes, bi-wiring is a necessary but not sufficient condition for bi-amping.
To amplify on kr4's answer (no pun intended):
If you biamp a speaker with two 200wpc amps, you could theoretically be sending 400w into one speaker. But it's pretty rare to drive full load into the tweeters, for example - it simply doesn't take that much energy to move a 1" silk dome a small distance. Even in a regularly powered setup with a 200wpc amp delivering an actual 200w to the speaker, very little of that power was going to the tweeter. (Let's imagine for this discussion that the speaker is a 2-way design, although the principles apply to any design.) That tweeter probably couldn't take 200w anyway, whether from an amp shared with the woofer or powered independently in a biamp configuration. I'm not sure whether my ears or the tweeter would blow first at 200w, but I'm not interested in finding out!
On the other hand, I'm sure it's possible that the woofer might draw 200W, but I think that usually that's where the design gets its power handling rating anyway. In such a state, the speaker might well be receiving maybe 220w and handling it quite well, since the tweeter probably is taking a few watts to run at a volume commensurate with that much bass.
Clearer?
To amplify on kr4's answer (no pun intended):
If you biamp a speaker with two 200wpc amps, you could theoretically be sending 400w into one speaker. But it's pretty rare to drive full load into the tweeters, for example - it simply doesn't take that much energy to move a 1" silk dome a small distance. Even in a regularly powered setup with a 200wpc amp delivering an actual 200w to the speaker, very little of that power was going to the tweeter. (Let's imagine for this discussion that the speaker is a 2-way design, although the principles apply to any design.) That tweeter probably couldn't take 200w anyway, whether from an amp shared with the woofer or powered independently in a biamp configuration. I'm not sure whether my ears or the tweeter would blow first at 200w, but I'm not interested in finding out!
On the other hand, I'm sure it's possible that the woofer might draw 200W, but I think that usually that's where the design gets its power handling rating anyway. In such a state, the speaker might well be receiving maybe 220w and handling it quite well, since the tweeter probably is taking a few watts to run at a volume commensurate with that much bass.
Clearer?