Basic's of Car Audio: Hardness Upgrades

So, you've got the tight ass whip with the 24' dubs, and the air ride suspension. Or maybe you've got the bitching '32 high boy with 350 hp. and candy paint!!! What do you do next? Well, if you're like most. The stereo at best is still stock. Being that you're pretty mechanically inclined, and pretty handy with a jigsaw, you want to build a modest stereo system for that Saturday Night Cruise. This is where a Hardness Upgrade will set you apart from, and ahead of the rest.