I have not owned bulls but I do own a northern pine snake. Same family, same attitude, same comical bluffing.

Check out this video, it is of an irate northern pine snake. Pits have unusually large glottis, which explains the really loud hissing. When they pull so much air back in, it sounds like chortling or choking or perhaps clicking.

https://www.youtube.com/watch?v=pgBtupYEMtw

I've been thinking of going for a bull for my next snake. Pits are so fun.