No, You Cannot Bi-Amp

Biamping made sense when amplifiers exhibited lots of IM distortion and a high powered amp was 60 watts. Not the case today.

True biamping means that you use a line level crossover. Such a crossover is usually superior to a passive crossover, and much less costly if the passive uses high quality parts. IMHO, the crossover is the chief advantage.

Subwoofers are almost always biamped.

Almarg's arguement makes sense to me. I believe that using two amps via the passive crossover ought to be called "dual amping" to distinguish it from true biamping using a line level crossover.

I performed testing to determine how powerful an amp is needed to drive my MG1.6 after lows are removed to an auxillary large cone driver system which I use as a subwoofer. I tested for a wide range of crossover frequencies. What I found was that the high frequency signal needed a lot more "power" than I expected. "Power" is in quotes, because what I was measuring was voltage peaks when playing music at high volume. Voltage swing is what is necessary to avoid distortion. Because the peaks are very brief there is no doubt that the power is actually low. But, because of the way audio amps are designed you have to buy power to get voltage.

Bottom line... don't skimp on the high end amp.