Ideas for Biamp with mc611 and mc275?

I applaud your initiative. Unfortunately, it is clear not many have ventured into this territory. There is very limited guidance, and Many I hear go back to the way it was

I’ve tried to learn about this and most are very unclear what Will happen. There are voltage differences between different amplifiers that will require level adjusting via crossover I guess.

And then you are faced with constant manipulation and in light of all the various recording Quality differences I am not sure if it’s worth going down this path. And you could have a result where it doesn’t sound very good

I looked at the amplifiers designed for biamping from McIntosh, 451 and 901 and they look very good. And expensive. However, these things generate a ton of heat. The 901 is the equivalent of a portable heater set to low continuously.

The 901 uses about 900 Watts from wall when in use which translates to 3000 to 4000 BTUs, which equates to about 10 bodies in a room. A human generates about 300 BTUs  sitting on the couch. And those that buy these amplifiers have dedicated air conditioning to minimize the heat impact. If you’ve ever had a lot of people in a room it gets very hot very quickly, and that’s what these amplifiers do to your room.

Quality tube amplifiers lose their appeal in this situation which is really sad. Maybe a lesser Power amplifier from Mac, ie 275 Will be perfectly wonderful for the upper range drivers. And I would especially be interested to know how biamping works out. I was tempted to try the mac stereo 1501 which is less powerful and generates less heat.

Another huge problem is all the additional cables you need to deal with, which offers all kinds of new challenges especially if you have a great speaker cable that now has to be supplemented with other cables.

So many issues.

Thank you very much for such an awesome comment, very helpful.

What crossover Device would make sense absent the Infinity IRS Servo Control Unit Device which I'm not sure can be used separate with other speakers, although it does seem ideally configured.

It is true I am very concerned about 901 heat generation, and I'm surprised you have no problems with that even with your 9 foot ceiling and larger room. Not sure if you've ever measured watts used from the wall when 901s are at idle and in use, but I have learned these things use about 1000 W while both units are in use, which is consistent with a portable heating unit set to low being run continuously..  I find it challenging to understand how these Amps can be used without on going AC to offset the heat. 
 

I did see you updated your pictures,  the 901 Amps look very nice, and I have noted the racks as well which seem ideal.

I have considered a 1501, or 2 275s, to go along with my 611 amps but the convenience of the 901 would clearly do a better job to achieve the biamp goal.