Don’t know if this subject has already been discussed but acoustics do appear difficult to pin down.
http://www.montana.edu/rmaher/publications/maher_aac_0406.pdf
There is another variable in there. Situation specific.
A bunch of mics, most likely EQ, compression, and digital reverb, a truckfull of power amplifiers, a bunch of subwoofer cabinets, and two flown line arrays, in that general order.
I hear inter-set muzak, after the band quit, so at least part of that sound reinforcement system was live, during the rampage, in the shooter’s ten ring.
They also don’t dicuss local slug impact or penetration excitations, or richocet, and at that angle of incidence, I heard a few whine on by, on video.