This is Jimmy Riddle and Jackie Phelps eefin and hambonin. It's not much, but not a single gallon jug was harmed during this post.
Before you do anything else, just listen to this. That's eefing, a 100-plus-year-old vocal technique from rural Tennessee that's, well, the original hillbilly beatboxing. The undisputed master of the art was Jimmie Riddle. His unique skill landed him recording* and TV (youtube) work. Want more weird sounds from the deep south? Try Hollerin & Whoopin and Ringing the Pig. *[warning: on the "Little Eefin Annie" page, avoid the "click here to hear Rolf Harris Eeefin'!" link: it's a pesky popup.