@djsundog I was curious about how one might defeat those and found this video (from a libertarian) where they built a homemade one and then tested it with various kinds of defenses.

TL;DR:

* The best defense is a standard pair of noise-protection headphones
* Adding a riot shield or something like it works surprisingly well, allowing the tester to get right up in front of the LRAD
* Foam earplugs are OK but not as effective as headphones
* Electronic headphones are worthless against LRADs

inv.tux.pizza/watch?v=CXKTBQBu