Thanks for the write up!
I wonder if the bass/LFE is as flat in your dad's as you have it graphed in your house. It could be you like a little more kick and the subs are not flat like it is in your room, but with 3 subs I would like to think it is realtively smooth.
I have always found surround effects to be better in larger rooms for some reason. I like Mojo's system better than mine for this reason, his surrounds have a more airy sound to them while mine are right next to me no matter what I do due to physical space limits.
A flat crossover for all the speakers is not unheard of as long as the surrounds can handle the lower frequency. Is Audyssey being used as well?
