The peanut gallery chiming in here... :)
If I were to use two amps on a speaker that had lugs for the bass module, and separate lugs for the mid + tweeter module, I'd find a cleaner way to bi-amp. I'd use this - on the Pass Labs XP-30 and XP-32 preamps, there is a master volume control on one set of XLR/RCA outs, then there is something called a slave pair of XLR/RCA outs. This "slave" output, its gain or volume control is controlled by a pair of small knobs on the front of the preamp; one can fine tune the "slave" output so that if one is using a less powerful amp for the mid/high speaker module, one can trim the "slave" gain/volume controls to obtain the right balance between the bass and mid/tweeter modules. It's a very trick feature built into these preamps. As the saying goes, I'm not sayin', I'm just sayin'... :)