I have the six by nines, the guy who owned the car decided to cut into the metal under the rear side windows and mount six by nines there, so i took them out and put the Kappas in, they sound pretty sick, but i have them running through an Amp so that must be why, no rattling of any type and they produce good bass, but im sure had they been put on the shelf then they would have had more bass, but hey what do I know....