I put in a new headunit today, cranked it up and I ran into a small problem which was there before I installed the new headunit. The rear two speakers sound perfect but in the front only the driver door speaker worked but it was a lot quiter then the rear ones. The passanger front didn't work at all. I opened the door up and found some1 installed some $40 walmart pioneers in there and the wires were not on the speakers. I attached the wires it sounded good but after a small ride it came off again cause the prongs on the speaker were broken. My question is, when one of the fronts don't work, would the other front sound like its quiter then the rear? Also, When I buy a amp for the speakers would the JL 450/4 be good match amp for 4 infinity kappas? Thanx