I've Boston Acoustic Pro Rally series speakers in doing my car, front and back. I have had them for 5-6 a few years they may have taken loads of loud music, rap and rock, over the years. I've had an amp installed in their mind the main time also. I am receiving a new car and am wondering easily should splurge and get new speakers or merely transfer them from my old car to my new car. They still sound very very good to me but that might be because I am so use for them. Does anyone know if speakers reduce quality after a while?? do amps?