Within a few decades into the twentieth century, acoustics had been transformed from a scientific field based on the understanding and performance of classical music into electroacoustics, guided by electrical engineering and media technologies. In my presentation I will trace these transformations of acoustics from the times of Hermann Helmholtz and Lord Rayleigh in the 1860s and 70s to the end of the interwar period at the dawn of World War II. While many physicists, among them CV Raman worked in the field of acoustics, it remains to connect the history of acoustics with a history of physics of the twentieth century at large.
The First World War made a profound impact on the soundscape of the twentieth century and its scientific study. Working on acoustical technologies for warfare, such as hydrophones for submarine detection and acoustic ranging of artillery and aircrafts, had turned the acousticians away from harmonics of musical instruments, and towards the complex noises of the battlefield. Research and development in electromagnetic theory, circuit design, telephony, and wireless prior to the war constituted a prerequisite. In the interwar period, acoustics research and the development of electroacoustical technologies in academia, industry and government laboratories flourished through the advance of public radio broadcasting and sound motion picture. If electrical instruments transformed sound into electrical vibrations and transmitted them as electrical signals, then scientists and electrical engineers came to understand sound propagation and manipulation in the notation of integrated circuits. Together, they brought about the electrification of the acoustics laboratory. This in turn changed the representation of acoustic phenomena in textbooks and classrooms. Consequently, electroacoustics became much more than a research technology and evolved from laboratory practice into a new language of sound. Beyond sound, notions of noise associated with the measurement process and information theory have moved to virtually all fields of science and engineering.