And here's a video in which he explains his "technique".
View this video on YouTube
And here are some things which are not as loud as his belch:
- A Jet taking off at 305 meters.
- A power lawn mower.
- A motorcycle.
- A farm tractor.
- A jackhammer.
- A garbage truck.
-A Boeing 707 or DC-8 aircraft at one nautical mile before landing.
- A Bell J-2A helicopter at 100ft.