Have a set of now "vintage" Polk S4's fpr the fronts. They look and work like new still so why replace them. I have a Atlantic Technology T70 Sub. What should my cross over be set at. It has a dial for anywhere from 60-120 I think its about 100 right now but I dont have a sound meter(radio shack thingy :) )or a test disc to be sure its right. I just figured with this S4 speaker there should be some kinad set level it should be at to be "right".