Walla

In American radio, film, television, and video games, walla is a sound effect imitating the murmur of a crowd in the background. A group of actors brought together in the post-production stage of film production to create this murmur is known as a walla group. According to one story, walla received its name during the early days of radio, when it was discovered that having several people repeat the sound walla in the background was sufficient to mimic the indistinct chatter of a crowd. Nowadays, walla actors make use of real words and conversations, often improvised, tailored to the languages, speech patterns, and accents that might be expected of the crowd to be mimicked.

Walla is called rhubarb in the UK where actors say "rhubarb, rhubarb", rhabarber in Germany, rabarber in the Netherlands and Flanders (Belgium) as well as Denmark, Sweden & Estonia, and gaya (がや) in Japan, perhaps in part reflecting the varying textures of crowd noise in the different countries. Other phrases are "carrots and peas", "watermelon cantaloupe" and "natter natter" (to which the response is "grommish grommish").

Walla is sometimes turned into an in-joke. On the UK absurdist comedy radio series The Goon Show, Spike Milligan would distinctly mutter "rhubarb, rhubarb" during crowd scenes. Spinning off from this recurring joke, the British comedian Eric Sykes (a collaborator and friend of the Goons) wrote, directed and starred in the 1969 film Rhubarb, in which all of the actors' dialogue consists of the word "rhubarb" repeated over and over. This gives the finished movie the general feeling of a silent film because it has no coherent dialogue, but with the crucial difference that the "rhubarb" dialogue still conveys the characters' emotions and moods.

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