I have $20 6x9's in a custom cab in my truck. I have no amp, the speakers are taking power from the rear channels, and the speakers in the doors (Pioneers) are dead. The cab has 3.2 cubic feet and is totally sealed. It sounds great! There's a shitload of bass you're not hearing from shitty speakers in the doors. The thing is, the bass is loud and clear inside the cab, but when you get out, the truck cab totally absorbs the bass. So, to surmize, if you like good sounding music while inside your truck, hell, 2 6x9's do the trick very well. But if you want other people to understand your taste in music you will need to have a little bit more. You guys would be surprised how much bass you can leach out of the stock HU and 2 20 dollar 6x9's.