Ah yes... Back in the day when I lived in a dorm room, I built a 12" sub to fit snuggly under the bed. It was an MDF 2.2cuft box using an el cheapo car sub tuned to ~28hz. Concrete wall on all sides (even the cieling and floor) except for a window and door. Room gain was insane, very much like in a car. :unbelievable: Thus the car sub actually worked really well in that environment. I didn't need much power, less than 50w was enough to get the most of neighbours annoyed. :devil:
The box was designed so the sub fired directly into the bottom of the mattress with about 1.5~2" of clearance. It took no space up in the room and another advantage was when watching movies, you would get some serious bed shaking happening even at low volumes. This is a good thing in a dorm room unless you want your neighbours to...

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