In this pioneering documentary, one of the earliest Soviet sound films, Shub shot a contemporary chronicle of the progress of establishing electricity across the Soviet nation, a struggle spearheaded by the Komsomol (the Young Communist League).
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<...>Direct sound recording and dubbed sound were combined with the symphonic music Popov scored for the film. The opening sequence - an "overture" that corresponds to the first movement of Popov's Suite - takes place in a studio where a musical performance is seen being recorded. Appropriately, the performance features a theremin, an electronic instrument invented in Russia in the 1920s. In his score, Popov offset the unusual sound of the electric theremin with human voices of soprano and tenor.
Popov's music attracted attention. Though it occupied a modest amount of time in the film, the score was viewed as a significant factor in its artistic impact. After seeing KShE, Sergei Eisenstein fired off a telegram to the composer, congratulating him on the "marvelous sound-sight victory."
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