I'm looking for opinions or any experiences with this type of box design.
This design is for a AA Assassin 12, 2.2 cu. ft. @ 33hz. Rear firing in trunk of 1998 Honda Civic. The purpose of the chamber is to protect the cone from skateboards, scooters, groceries, or whatever else finds its way into the trunk.
My train of thought is that the open chamber increases and equalizes distance to the rear wall of the trunk as compared to the port. And will minimize cancellation from a sideways or upward firing sub where some soundwaves travel directly into the passenger area and some are reflected from the backwall of the trunk.
Opening of the chamber is roughly 70 square inches or about 60 pecent the surface area of the speaker cone.