When I was a kid my parents both had 1985 Buick Regals with this alarm siren on it. It was made by a now-defunct company called Chapman, and it was an air-horn siren that would just obliterate your ear drums when it operated.
I actually found an unused, brand new kit on ebay which I bought for $10.00 and now am in the process of trying to figure out how to integrate this siren into my Camaro's factory security system so if someone breaks in not only does the factory horn honk, but this siren wails!
https://www.youtube.com/watch?app=desktop&v=mVRYIUrsMNk