I've got a 2006 Trailblazer...the stock speakers were dying. On a budget and don't need anything fancy so I replaced the front door speakers with a set of Scosche's from walmart a few weeks ago. Surprisingly, they didn't really sound bad at all, so I went back yesterday and got another pair for the rear doors. Overall, sounds pretty good but now the drivers door speaker has almost no bass coming through compared to the other three. I took the door panel back off and I can see the woofer moving, so it's still getting a signal.