That brings to mind an incident that happened a year or two ago.

I was in the back of the house doin' whatever, when suddenly it sounded like an automobile had breached the front room wall!

Turns out it wasen't quite so severe. Simply my youngest Grand Daughter grabbing a handfull of volume control during a bassy part of a movie.

The next day I was on-line looking for the correct Thiele Small parameters for known size empty box.