WOW, that is so cool. I was actually looking at something like that on eBay last week. A 12" Eminence and 5 quality watts is plenty for in the house. I bet it sounds fantastic. I didn't realize it was that big either.
They can't hear it, I'm up in the loft and these brick houses are almost totally soundproof. I don't think I've ever heard out neighbors unless the doors and windows were open.