1: Dryfire - Easily the loudest and most boisterous of the 2. Pure farts with no fecal matter; these happen from pushing hard or being constipated. These are so loud they could be heard from 30ft away or more with crystal clear clarity.
2: Explosive - These aren't as loud, but way nastier sounding. These happen with the occasional normal shit, and are 100% bound to happen with bad diarrhea. One of the nastiest sounds on Earth, but hilarious if you manage to hear them coming form someone else.