Ideas for Biamp with mc611 and mc275?

The Men 220 has crossover controls that you will need to send the signals from the 2 different amps so that they do not try and play the same signals to the speakers. 

Maybe trying a tube pre with the Mc611's?

I’ve done this for years and it sounds excellent. are use the Macintosh C50 pre.  Speakers are Tekton Moab with the bi-amp crossover. Everything sounded balanced and perfect, except that I had cleaner base, more base, actually and warmer mids and Highs.  I have to believe that the mackintosh MC 451 amp is maybe a little bit better because it was designed exclusively for the task at hand.  I believe it’s called horizontal bi-amping.

@raysmtb1 

What crossover device do you use for bi-amp?

I saw your system, is mc275 used for the higher ends?

My speakers were designed as a bi-amp speaker. There were four connections on the back of the speaker cabinet instead of 2. If that’s what your speakers have been, you’re fine the speaker company has designed it to be crossed over inside the speaker. When the signal gets sent from the amplifiers, they both send a full signal. The crossover is what filters out what the speaker wants. If you don’t have a speaker that is designed with that kind of crossover then you’re gonna need to rip out the existing crossover and use an electronic crossover.