Unknown with the current Khorns. I would say, "No."
I owned the 60th Anniversary Khorns which were sealed in the back but ended up selling them.
Khorns are very room dependent and need to be placed right up in the corner so I am not sure why you are so concerned about whether they are sealed in the back.
I also owned the LaScala II's which were very nice speakers. If only I knew about electronic crossovers and subs at that time.
