Definitions for "Bi-amping"
Using two power amplifiers to drive one loudspeaker. One amplifier typically drives the woofer, while the second drives the midrange and tweeter.
In loudspeakers that have the appropriate connections, bi-amping is the practice of using two power amplifiers to drive a single loudspeaker, one for the woofer and one for the mid/high frequency section. Normally, the internal passive crossovers are used so that the manufacturer's system design is left intact (assuming that the amplifiers gains are identical, and they are in phase). In large professional systems an external electronic crossover is often used, in which case it is essential to equalize the system afterwards, since the user is really designing the loudspeaker system from the ground up. See: Bi-Wiring.
In bi-amping, the woofer and tweeter of a speaker are driven by signals from separate amplifiers (or amp channels). This way, both low-frequency drivers (woofers) and high-frequency drivers (tweeters) receive dedicated amplification.