I agree with everyone else who said the M22's are too small for the room. I'm not sure what the angle of the slope is, but off the top of my head, the room is roughly 6000-7000 cubic ft. I doubt the M22's were designed for rooms larger than 2500 honestly, but I could be wrong. If your friend decides to stick with Axiom, I think the M60's would be his best bet. It would work well with the existing receiver, since it is an 8ohm speaker, and is meant for larger rooms. The M80's could also work, but he would be using his receiver to drive two 4ohm loads (unless he decided to get an external amp) and that would put considerable strain on the Yammie.

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