Contributions
Hornbostel did much work in the field of ethnomusicology, then usually referred to as comparative musicology. In 1906, he was in America to study the music and psychology of the Pawnee people, native Americans in the state of Oklahoma; he had by that time already studied the native music of Tunisia and of South Sea Islanders.
A highly regarded teacher, Hornbostel's students included American composer Henry Cowell. Hornbostel specialized in African and Asian music, making many recordings and developing a system that facilitated the transcription of non-Western music from recordings to paper. He saw the musical tunings used by various cultural groups as an essential element in determining the character of their music, and did much work in comparing different tunings. A lot of this work has been criticized since, but in its time, this was a rarely explored area. Hornbostel also argued that music should be a part of more general anthropological research.
Hornbostel also contributed to the theory of binaural hearing, proposing the theory of interaural time difference as the main cue, and developing sound localization devices (for finding the directions to artillery, aircraft, submarines, etc.) for the German war effort during World War I. With Max Wertheimer, he developed a directional listening device that they referred to as the Wertbostel.
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