Well a bass horn for 30hz is a monster, better go Bass reflex!!
If you are going for that BMS driver better try to get the 340 azura horn or even the 160 and cut driver down to 300hz, it has a coaxial tweeter...I heard mixed things about BMS...
Up to 300hz the JBL 15" driver will do fine.
For 800hz I would get something like this:
http://www.usspeaker.com/beyma%2012BR70-1.htm
If you are going for that BMS driver better try to get the 340 azura horn or even the 160 and cut driver down to 300hz, it has a coaxial tweeter...I heard mixed things about BMS...
Up to 300hz the JBL 15" driver will do fine.
For 800hz I would get something like this:
http://www.usspeaker.com/beyma%2012BR70-1.htm