Class A or Tube (or else?) for high pass (bi amp) of Infinity Quantum 2

Accordign to the factory published diagram, tweeters are all the same.

Good, I was afraid they did them like the RS1B where one is driven at full volume and the rest are attenuated. 

Accordign to the factory published diagram, tweeters are all the same. There may be a version for the 3+1 (rear firing EMIT). 

I would try with active 2 way signal split first (not sure what to do with the 'internal' 2 way paths for the bass). But can ALWAYS just run passive 2 way (some versions of the Quantum 2 HAVE already binding posts for passive 2, and I am rebuilding the crossovers to factory spec for that reason). 

BTW, do you understand the crossover design? Not sure but I think it does more than just split the frequencies. I think the levels of each tweeter are different but I could be wrong. 

It wasn’t the woofer that sucked all the power from the amp. You don’t want to under-feed the other drivers, good way to blow the tweeters. Not sure what happens when you bypass the factory crossover probably will make it a bit more efficient.