would it sound better if you open up the arm rest that leads to the trunk thats in the middle of the back seats? will it be better because it now has more air inside the car? going to try this with two 10" RF punch. will this going to be a good or a bad idea?

 

yes.. it would be better because now the bass is inside the cabin of the car.. The Maxima is designed quite well acoustic wise. I think that 1 12" sub with the armrest open is enough to get decent bass.

 

I noticed no difference at all with the armrest down, so I keep it up.

 

I'll second that, that it probably won't make much difference...

I never noticed a difference with my Stealthbox.

From what I've read in various places, only if your car has all steel between the trunk and passenger compartment, should you worry about making a hole. (European Luxury Sedans, in general, are all steel)

For the Maxima, with cloth, foam, and plastic, with a few bracing stamped steel bars, it won't make much of a difference