I have four of the Alpine type S's http://www.onlinecarstereo.com/CarAudio/ProductDetail.aspx?ProductID=16415 and they aren't hitting at all in my car with this head unit http://www.onlinecarstereo.com/CarAudio/ProductDetail.aspx?ProductID=17690. I would like to know what amp would work well with these to make them perform the way they were meant to.