In his book And Here’s the Kicker, Mike Sacks interviewed 21 humor writers about their craft. (Sacks writes funny things himself.) As part of his research, Sacks interviewed Ben Glenn II, an expert in the history of canned laughter, and the result is now up at the Paris Review blog. A piece:

Who invented the canned-laughter machine?

Actually, its official name is the Laff Box, and it was invented by a man named Charles Rolland Douglass. He served in World War II, and when he returned to civilian life, he worked as a broadcast engineer at CBS. Douglass was responsible for everything from recording sound levels during production to adjusting them in post-production. [. . .]

Where did the laughs on the Laff Box originate?

Reportedly, the earliest reactions came from a Marcel Marceau performance in Los Angeles in 1955 or 1956, during his world premiere North American tour. This would make sense, because Marceau was, of course, a mime, and therefore, the only sound in the theater was the audience’s reaction.