Edwards Signaling makes an 8-headed omni-directional dual-tone airhorn for industrial fire signaling applications. They sell the K4-12 (which has a frequency of 311Hz and 370Hz) and the K4-25 (which has a frequency of 370Hz and 622Hz). They also sell a smaller 4-headed single-tone version, the K4-1 (311Hz).
Some fire alarms in the 80s-90s had really LOUD horns on them. In fact my PTSD of fire alarms comes from them going off at school. They are definitely quieter nowadays and less jarring.
I’ll bet Thomas Edison was “bored”, then the light bulb was invented. Lots of good things can happen when productive people like Nic need things to do.
This was a great video as always!! Airhorns wouldn’t be a bad idea being their way louder, especially in a louder environment!! Very interesting!! Keep the awesome videos coming!!