I am very curious about these. My receiver does not support them, at least I do not think it does (Yamaha RX-v1000). I hear you are supposed to space these further apart and higher up than main front L & R speakers. Do they really add that much? I have a 7.1 set up now and I guess adding these would take me to a 9.1 system. Please post your reviews using front effects speakers. Thanks all...I may just have to upgrade my receiver now.