A cap is always a good addition to a system, but if your only running door speakers it's not a priority, you aren't going to be drawing huge amounts of current like you will when a sub is trying to hit a big bass note. Check out the group buy section if you are looking for a cap, Knukonceptz will sell them to us for 69 bucks if we get enough people. Here's a funny one, I was just at Circuit City today because I had a $15 gift card to use. they wanted $200 for a monitor top Cap!!!! Outrageous!!!
