You know what I mean: the sound of a couple of drum beats and (usually) a cymbal after a joke.
Who first decided that the audience needed an auditory cue that they’d been told a joke?
Um. Jimmy Carter? Badum pssht.
I was ready to say “probably Gene Krupa”, but I see this is a different area.
And, a rimshot is actually…oh, never mind… 
It probably comes from vaudeville or the comedy circuit in the Catskills. I know that there was a joke back when my Dad was a lad (somewhere around 1940) which went:
“Two elephants fell off a cliff. Bom bom” (The last being an attempt to mimic the sound of the drum for a version of a rimshot).