Back when I was a tad younger.....
I was using the same speaker setup WITHOUT the sub woofers.....listening to Steven Stills...REALLY LOUD....
All of a sudden I heard something that was distinctly NOT musical... I turned around, and the music had imploded one of my 4 foot sliding glass doors! All that was left was a pile of little pieces of glass, and a big hole to the outside....
100% truth.