For more on the Laff Box and how America fell in and out of love with the laugh track, listen to Decoder Ring, a new podcast from Slate.

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Imagine that television is brand-new. You’ve just gotten your very first set. It weighs a ton and it’s the size of a bureau, with wood paneling and a couple of dials on the side. You set it up in the living room, and you call in the whole family and turn it on.

The Jack Benny Program is on. Originally a hit radio show, the series starred Jack Benny, a onetime vaudeville performer and comedian, as a version of himself, a radio star. And now that show from the radio is on your television, and even though you’ve heard it before, you’ve never seen anything like it.

Before, when you watched a performance, it was in public with an audience, and now it’s happening in your house. Think how strange, how new that must have been. And if you were able to listen, you would hear something recognizable, something reassuring, something that told you what you were watching: laughter.

That’s how most early TV comedies were recorded, in front of a live audience, usually in studios in New York. But by the early ’50s, as the TV industry moved away from New York and into Hollywood, executives wanted to move away from the traditional approach of broadcasting what amounted to live stage shows. They wanted to shoot comedies on film, comedies that were not live but that still sounded live.

The solution to this problem was the laugh track. And the person who came up with the solution was Charles Douglass.

Douglass was a mechanical engineer who had worked on radar for the Navy in World War II, so he knew his way around audio and electronics. In 1950, The Hank McCune Show, a mostly forgotten series from NBC, had used a rudimentary laugh track. But by 1953, Douglass had developed a better way to insert a laugh into a show. If you’ve ever watched an old sitcom, you’ve almost certainly heard his work.

Charlie Douglass played his Laff Box like it was an instrument.

I asked Ron Simon, curator of television and radio at the Paley Center for Media, formerly the Museum of Television & Radio, about him. “Charlie Douglass took the concept of just adding laughter, probably from a transcription disk, and created a machine that could do it.” he said. ”He created this little box using laughter from Marcel Marceau and from Red Skelton from the silent sequences and created tape loops that could then be injected into film comedy to make it a live experience.”

Douglass pored over these laughs at his kitchen table night after night, splicing them into analog tape reels that could be played on a patented device Douglass built himself out of household appliances, organ parts, and vacuum tubes. This device was about 3 feet tall, the shape of a filing cabinet, very heavy, and had slots for 32 reels, which could hold 10 laughs each. It was officially named the Audience Response Duplicator, but it became known as the Laff Box.

The Laff Box, Simon said, “was this weird machine that’s closer to, we’ll say, steampunk than it is to modern electronic technology. It looks so primitive … like, an adding machine where you just press the dials and laughter would happen. Eventually it would evolve into more of a typewriter thing where you would punch keys.”

The Laff Box could chuckle. It could guffaw. It could laugh with sighed relief. It even had a reel, controlled by the foot pedal, that was only titters, one person lightly laughing at a time. At its most sophisticated, the box had 320 laughs. It could play one laugh at a time by pressing one key, or by pressing multiple keys together, it could play a bunch of laughs at once.

Because Laff Boxes were patented and handmade by Douglass, it wasn’t as though just anyone could make or use one. There were only a handful of working models at a time, and Douglass essentially had a monopoly on the process. By the 1960s, almost all sitcoms were single-camera shows filmed without an audience and tricked out with a raucous Charlie Douglass laugh track. The boxes supplied laughs for tens of thousands of episodes of television, everything from The Munsters, Bewitched, The Beverly Hillbillies, and Gilligan’s Island to The Mary Tyler Moore Show and Cheers. For decades, their sound was ubiquitous. But Douglass didn’t want to talk about his device.

Douglass hardly ever gave interviews or spoke about his work. In a 1966 piece from TV Guide, titled “The Hollywood Sphinx and his Laff Box,” Dick Hobson described the mystery surrounding Douglass and his device: “If the Laff Box should start acting strangely, the laff boys wheel it into the men’s room, locking the door behind them so no one can peek. … I mention the name Charlie Douglass and it’s like Cosa Nostra, everybody starts whispering. It’s the most taboo topic in TV.”

Every knock on the laugh track you’ve ever heard—it’s fake, it’s corny, it’s cheating, it’s not funny, it thinks audiences are dumb—has been around since the very beginning. And that’s part of the reason for Douglass’ silence.

But listening to Douglass’ laughs changed how I thought about them. I’ve always prided myself on being open-minded about the laugh track: A funny show is a funny show, with or without one. But even so, I always thought of it as an automated, mechanical thing. But it isn’t really that at all: It’s a craft. Charlie Douglass played his Laff Box like it was an instrument.

I recently listened to one of Douglass’ laughs that was often heard through the late ’60s and ’70s, including in the pilot for MASH. I especially love the laugh that trails off at the end. It tells a story. There’s a joke, but one guy in the audience doesn’t get it right away. He’s a split second late, and then he laughs a little bit longer. Charlie Douglass wasn’t just a sound engineer; he was a psychologist.

The rap on the laugh track is that it’s fake laughter from a fake audience, but that’s not quite right. The laugh track doesn’t just represent a bogus audience; it represents an audience of one. Of Charlie Douglas. He definitely goosed laughs at producers’ instructions, but to a large extent, he and the people who worked with him followed their guts. It’s incredible that one man’s taste and sense of humor were so important in pacing an entire type of television comedy—but it’s true.