Clap-o-meter

A clap-o-meter, clapometer or applause meter is a measurement instrument that purports to measure and display the volume of clapping or applause made by an audience. It can be used to indicate the popularity of contestants and decide the result of competitions based on audience popularity. Specific implementations may or may not be based on an actual sound level meters. Clap-o-meters were a popular element in talent shows and television game shows in the 1950s and 1960s, most notably Opportunity Knocks, but have been since been supplanted by other, more sophisticated, methods of measuring audience response.

One of the first appearances of a clap-o-meter was in 1956, on the British TV game show Opportunity Knocks, developed and presented by Hughie Green. The clap-o-meter itself was a wooden box labelled "Audience Reaction Indicator". The prop is now part of the collection of the National Media Museum, in Bradford. Clap-o-meters were used in many other TV shows and at live events.

In 1989, Green unsuccessfully attempted to sue the New Zealand Broadcasting Corporation for copyright infringement over a similar programme. The clap-o-meter was one of the distinctive features of the format by which Green sought to define it as copyrightable. The courts found that a loose format defined by catchphrases and accessories, such as the clap-o-meter, was not copyrightable.

Clap-o-meters continue to be used. They are often regarded as a novelty or item of amusement rather than an accurate method to measure popularity. Even so, they are sometimes used to judge winners in fairly serious competitions such as battle of the bands competitions.

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