Built by Friedrich Trautwein in 1928 at the Hochschule für Musik in Berlin, Germany, the Trautonium was designed as a performance instrument. A performer pressed a finger down at a certain position on a wire to produce a tone at a particular pitch. Loudness was controlled by pressing a bar. Timbre was controlled via switches that filtered an initially complex waveform.
Oskar Sala expanded the Trautonium to create the Mixturtrautonium and used it to compose sound effects for films, among them Hitchcock's The Birds.
[Read more & listen - via Orpheus Music]