Pjam said:.. the simplest way to avoid more sound coming from rear is thru the fader function of HU (ie. front, rear).. thats if the rear's sound is more audible than front..
most often, aftermarket well-known speakers perform better than stock speakers, hence the music seems to come from the rear, if u r sticking to the stocks for fronts...
anyhow, it also depends on your preferred setup.. some like their music from the back, i think :D