I have 5 in my dining room (system 11s) and 8 in my living room, 2 in my entry hall along with a 100 CD jukebox. All over my basement with 15 to 20 pins down there at any given time. If my floor joists aren't strong enough to support that...then it needs to fall so I can rebuild it bigger and stronger!! (cue the SMDM music!!)
Phoebe