Laugh track

A laugh track (or laughter track) is a separate soundtrack for a recorded comedy show containing the sound of audience laughter. In some productions, the laughter is a live audience response instead; in the U.S., where it was most used, the term usually implies artificial laughter (canned laughter or fake laughter) made to be inserted into the show. This was invented by American sound engineer Charles "Charley" Douglass.

The Douglass laugh track became a standard in mainstream television in the U.S., dominating most prime-time sitcoms from the late 1950s to the late 1970s. By the 1980s, the Douglass family was eventually outrivalled by other sound engineers who created stereophonic laugh tracks different from the original analog track. Also, many single-camera sitcoms by this time started diverting from a laugh track altogether to create a more dramatic environment.

Before radio and television, audiences experienced live comedy performances in the presence of other audience members. Radio and early television producers attempted to recreate this atmosphere by introducing the sound of laughter or other crowd reactions into the soundtrack.

Jack Dadswell (also known as the "Traveling Reporter" by Time magazine), former owner of WWJB in Florida, created the first "laughing record".

In 1946, Jack Mullin brought a Magnetophon magnetic tape recorder back from Radio Frankfurt, along with 50 reels of tape; the recorder was one of the magnetic tape recorders that BASF and AEG had built in Germany starting in 1935. The 6.5 mm tape could record 20 minutes per reel of high-quality analog audio sound; Alexander M. Poniatoff then ordered his Ampex company to manufacture an improved version of the Magnetophon for use in radio production.Bing Crosby eventually adopted the technology to pre-record his radio show, which was scheduled for a certain time every week, to avoid having to perform the show live, as well as having to perform it a second time for West Coast audiences.

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