Peter Donhauser
Concerto for 300 Volts, 20 Amps and Orchestra

mixture trautonium: wiring diagram from the patent, 1952The mixture trautonium is a further development of the radio trautonium that Oskar Sala began working on for the Reichsrundfunkgesellschaft in 1935. He reported on the work in a detailed article in Neues Musikblatt, describing the two-manual design as the result of years of technical experience with the specific practical and musical requirements. Sala used the instrument for a number of radio broadcasts in Germany in 1938/39, consisting mainly of works for piano and trautonium, either arrangements of virtuoso violin or wind music or new compositions, above all by Harald Genzmer.

The radio trautonium being hardly suitable for transportation, Sala built himself a two-manual concert instrument for his many concert tours, which continued well into the war period. The instrument survived the war, and already included simple mixtures, although the adjustment of the notes was still cumbersome. This instrument was then the basis for the development of the mixture trautonium in the years following 1948. The work was helped along by the accidental discovery that a specific valve switching was particularly suitable for the synchronization of the subharmonics (without a fixed frequency locking it is not possible to synthesize harmonious sounds). Sala filed this invention for patent in Germany and the USA. Since a separate sound mixture can be set on each of the two manuals (a resistance wire over a metal rail, as with the Volkstrautonium), it is possible to create a very varied and colorful sound.

It was for this new instrument that Harald Genzmer wrote his Concerto for mixture trautonium and large orchestra in 1952, the second work he composed for Sala. The first (first performed in 1936, subsequently revised and successfully performed in the Berlin Philharmonie in 1940), was for the older concert trautonium. An even larger work was composed for the instrument, Jürg Baur’s Concerto for mixture trautonium and string quartet (1956).

Alfred Hitchcock and Oscar SalaSala subsequently abandoned the world of concerts and discovered that of the film. He is famous for his synthetic seagull calls in Hitchcock’s The Birds (1963) and for the two award-winning soundtracks for Stahl, Thema mit Variationen (1960), A fleur d’eau (1963) and the Edgar Wallace film The Curse of the Yellow Snake (1962). He provided the electronic sound effects for numerous other films (allegedly over 300), extending the instrument by adding echo devices, frequency converters, audio processers etc. A demonstration of the instrument in 1980 persuaded three professors of the Deutsche Telekom University of Applied Sciences to build a microelectronic mixture trautonium according to the acoustic specifications of Sala’s design. The project was successful, and Sala used the instrument until he died in 2002.

However, another project was not so successful. In 1948, Sala was asked to build a quartet trautonium for the radio. Although, after much delay he produced a laboratory model, it was still not a workable instrument in 1957. The Rundfunk- und Fernsehtechnischen Zentralamt der Deutschen Post (already part of the GDR) then decided to develop an instrument itself, the subharchord (a combination of “subharmonic” and “Akkord” or chord), a few models of which were sold to innovatory radio stations.


1 Ein neues elektrisches Soloinstrument, in: Neues Musikblatt, May/June 1938, p. 5.

2 Patents DE 917470 (1952) and US 2740892 (1956).

3 See Oskar Sala im Gespräch, in: Peter Frieß, Peter M. Steiner (eds.), Forschung und Technik in Deutschland nach 1945, Bonn 1995, p. 215ff.

4 See Peter Donhauser, Elektrische Klangmaschinen, Vienna 2007, p. 228f.