I have a 2007 Dodge Dakota crew cab and the first thing I did when I got it was put in Alpine speakers. I'm still not happy with the sound, I want to be able to put it louder without the music sounding raspy, so I want to hook an amp up to my 4 speakers. My problem is I can't remember the exact model of the speakers to see the watts of them, so first, do i need to know the specifications before buying an amp? Second, does the brand make a difference in amps because I see amps from brands I never heard of with high watts for cheap. Appreciate any help. thanks.