Canned laughter is also for the timing. Sitcom actors can’t hear the tv viewers laugh, but they, like stage actors, still need to wait for the laughter to end before they deliver their next line. That’s one reason for having canned laughter - but of course, movie comedies manage their timing without canned laughter, so it’s also there to make the home audience laugh.
I think this is is response to this Staff Report.
How can this be, if the canned laughter isn’t added until after the scene is filmed?
Yes, wrong forum, I’ll move it over.
your humble TubaDiva
Careful scripting?
It’s true that live-audience laughter acts as a cue for the actors, but that’s more true for theater than it is for TV.
Many TV soundstages used for sitcoms set the audience off a good bit from the actual stage. There are also crewmembers in between and a lot of activity takes place, even during shooting, and the actors (or “talent”) are more concerned with that than they are with listening for audience reaction, so the idea of laughter for timing and cues isn’t as major here.
Robin
JOOC, MsRobyn, did you mean to say “Not being a big fan of Scooby Doo myself, I can understand why a laugh track was needed” instead of “can’t”?
Nope. I meant what I wrote. I’m really not a fan of “Scooby Doo”, and I can’t understand why there ever was a laugh track. It’s just not that funny to me. :shrug:
Robin
I cannot stand laugh tracks. If a show is funny, then it shouldn’t need them. (The simpsons, scrubs, etc). I can’t pay attention to the show. I keep just hearing all the fake laughter and it annoys me to no end.
When I come across a MASH episode I like, I’ll turn it off immediately if it’s one with canned laughter. The show’s funny enough without it.
Just out of curiosity, how did the OP (and those responding) find this Staff Report? It’s not dated until next week (Aug. 16th) and I can’t find it on the SD Front Page. Is there someplace where these are posted before they go on the Front Page?
Primeval TV star Milton Berle claims credit for inventing a sort of flashing light device that blinked to simulate the audience laughter. Performers could judge the “laugh” by watching the length and intensity of the blinks.
I don’t know if it’s still used, or if the performers simply pause as long as they want the laugh to be.
This was the Staff Report that came along with today’s mailing list e-mail. It surprised me, too.
Robin
And, in response to kunilou, most canned laughter is digital, which means that it can be easily edited to fit a desired length.
Robin
I, too, hate canned laughter. Whoever was in charge of editting in the laughs for Monty Python did a horrible job of it – it’s always too loud and too long, sometimes drowning out the next joke.
The “laughter begets laughter” idea was, apparently, used by Mark Twain. In Roughing It, Twain describes returning from his trip to Hawaii as a newspaper correspondent and coming up with the idea of becoming a lecturer. He wrote some material, hired a hall, and advertised his lecture but was very nervous that people wouldn’t like him. To allay this fear, he hired a couple of confederates to sit in the audience and laugh like mad at his funny stories. A glance from Twain was to be the cue to laugh.
In the book, Twain claims that at the end of a particularly solemn part of the lecture that he was very proud of, he accidently glanced at one of his confederates (with a “hair-trigger laugh”), who proceeded to laugh. Everyone else took their cue from him and laughed too, and Twain’s serious, solemn story drew the biggest laugh of the night.
Twain must’ve stretched the truth a bit, of course, but it shows that the idea of the laugh track came way before TV. 
If you’re referring to the Flying Circus television series…
The editing might have been off sometimes, or maybe a lot, but I don’t think the laughter was canned. Their skits were recorded in front of a studio audience, interspersed with pre-filmed sketches and animation that was also shown to the same audience.
One quasi-exception was the “Attilla the Hun” skit (and there may have been others), in which they deliberately played around with canned laughter: exaggerating it, cutting it off very suddenly, and in general making it obviously artificial. You can still hear real laughter from the audience though, in between those bits.
You can also tell that the laughter was natural by watching the very early and very late episodes, when the audience hardly laughed. If Python had been willing to use canned laughter, they presumably would have used it then. In the early episodes, the material probably fell flat because they had the “wrong” sort of crowd in the studio, and maybe because they were still finding their rhythm. In the later episodes it was because they were starting to run out of ideas, and the sketches were often incoherent. That, and John Cleese had left the troupe. (Much of all this is my personal opinion of course.)
There’s a link on the Front Page to subscribe to a mail list to get advance notice of the next weeks columns. Be the first on your block…well, one of the first.
I was, and thank you for correcting me.
I just now read Robin Cartwright’s Staff Report article. (Sorry — I’m a bit behind.) I’m intrigued by this statement:
So what would distinguish audience laughter in different accents, assuming you can’t hear any specific spoken words?