Hi Jim,
The ACE650MKs are the top of the line and feature Kevlar cones, butyl rubber surrounds and an elaborate crossover network. Typically in a bedroom, you want to be able to listen while in bed so a pair of the ACE650 placed 12 feet apart with a speaker mounted above the bed on either side would be ideal, making sure to pivot the tweeter facing down towards the pillows. The ICE840 may be a better choice for outside where you will need a broader sound field. Both speakers are an excellent choice.
I hope that helps
Tim L