Blacthorn

I am sure this is elsewhere in this forum, so please forgive me. What I want to know is what is the minimum size room you should have for KHorns? also what would be the optimum size? I am probably slightly off my rocker, but I am considering purchasing Khorns (probably 2 pair) for HT. Then probably would try and find either a LaScala or Belle for center channel. Okay yes I know this is probably overkill to say the least, but hey you gotta dream right? Anyway, thanks for any ideas.