I'm interested in installing a sub but I don't want a space hogging big ass box in my trunk. I'm not really big into audio but I do want to add some low end punch without being crazy loud. My idea is to install a free air sub directly behind the fold down armrest in the trunk. This will allow the bass to enter the cabin while the armrest is down and the little door that goes into the trunk is open. Will this work? Again I'm only interested in adding some good bass without being the King of Krunk. Any of you audiophiles have any suggestions? Crutchfield sells a Kenwood free air sub that I think would work good. Can I use that with a good amp (suggestion welcome on a amp also) and also use the rear 6x9's? I dont know much about car audio so help me out with some good intel. Thanks!