how much difference does it make? ive heard of people using spray in sound deadener but ive never heard a system that had it done... does it really improve anything?
General box design can help you here. The idea is to make the flow of air in/out of the box as smooth as possible. Try eliminating corners by adding wood wedges in those spots closest to the port, resin the inside and shear placement of the port can make a huge difference too. Polo..