Eldartford: The best illustration of what my set of large subwoofer drivers can do is to play pipe organ music. Not all organ music has loud bass, but when it does you should FEEL it in your stomach, and my system does achieve this. Also, when the SPL is moderate, the large drivers are loafing compared with small drivers that would be generating large excursion, with attendant distortion.I would be more concerned with the structural integrity of my house than with the neighbors!
Obviously I could not enjoy such a system if my nearest neighbor were not about 600 feet away with woods in between the houses.
My closest neighbors are about 200 feet away, through the woods. However, iirc I have only played my 1978 direct-to-disk recording of "The Power and the Glory," on M&K Realtime, once. During which playing the windows in the room were set into easily audible vibration, and after which I found a couple of paint chips on the floor that had formerly been part of the ceiling! :)
Best regards,
-- Al