No, You Cannot Bi-Amp

Take the money you save on extra amps, cables, and jumpers and buy a nicer amp, probably with more power so you don't give up any dynamic range.

Sonic benefits:

Transparency
Dynamic Headroom is not jeopardised by either descrepancies of amplifiers or decreased input amplification impedance
Tonal balance

Negatives:

1. 2 cheaper lower powered amps can have more power than one nicer more pricey amp so there are limitation on available options that should IMHO be present in complexed speakers
2. If two amps are absolutely identical, the benefits could be identical to a single amp only with increased power.
3. Y-connector on preamp output may be necessary that decreases an input impedance of amplification again limiting the dynamic headroom.

Ahendler's comment is right on target. The series crossover is not amenable to biamping. My opinion of the crossover in the 3.7's is that is a pretty significant improvement over the stock crossover in the 3.6. I drive mine with Cary 500 MB's, which delivers sufficient current to drive the speakers without biamping. I have heard neither the 20.1's or the 20.7's so I can't comment on those two. Let your ears be the judge.

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I wouldn't know a crossover from a crossbow. I want to get myself a pair of the 20.7 and I'm glad to know that the new design allows you to power the speaker with one amp without having to worry about whether it would sound better with two amps. I'll just make sure the my amps have plenty of muscle at 4 ohms in order to dominate the speaker.
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