How to make an Air cannon sound cooler/louder?

[jackssmirkingrevenge]

Do you know where they are bought commercially? I'd like to show people that they have an air deterrent project and they need to increase the noise from the markers.

If you search for "airsoft amplifier" on places like eBay or Aliexpress you'll find plenty.

Other useful key words include "Sound Hog", "KX3", "KX5" and "KFH"

[hectmarr]

I found some plans for a 3d printer, I leave them here, and a video of how much this type of device increases the sound, from about 81dB to 99dB. Perhaps it will help the author of this topic.
https://cults3d.com/es/etiquetas/resonador
In the video, testing starts at 3:20

[Luke31]

Maybe a metal cone/cylinder at the end of the barrel will make the most noise. Like when you hit cymbals on a drum set.