I found the matching the compesssion driver to the low end is the weak link, can sound like 2 diffrent systems going at once. Also the low end might be handeling too much mid frequencys. Ive used MANY compression driver systems the link is my system now.
http://home.comcast.net/~jtgale01/andys_room.htm
http://home.comcast.net/~jtgale01/andys_room.htm