5 Contemporary Research and the Application of Scientific Sonification

Since the 1950s, the development of computer technology has led to a fundamental shift in dealings with existing data material. Increased performance has made it possible to process increasingly voluminous data sets. The use of time-discrete signal processing was the basis for the emergence of sonification research, as it — at least theoretically — made possible the conversion of any kind of data into audible information.^[13] Thus, the first applications to include auditory displays were developed, whose purpose was to support communication at the human-machine interface. As early as in 1958, an early form of the auditory display was used in one of the first fully transistorized computers, Heinz Zemanek’s Mailüfterl.^[14] In order to remotely monitor what at the time were still considerable computing times, the Mailüfterl was connected to a telephone; in this way, one could listen from home to the algorithm while it was working.^[15] A continuous tone signaled that the computer had crashed. Different tone sequences allowed staff to discern where in the program the computer was at any given time. It was also in the late 1950s that purely analog tests were conducted to acoustically display and investigate earthquakes. At the time it was common practice to store the registered data on magnetic tapes, which, like audiocassettes, could be played back at a higher speed. This shifted the earthquake’s oscillations into an audible range.^[16]

Today, the concept of auditory seismology is associated with research projects by the geophysicist Florian Dombois, who advanced the sonification of earthquakes both for science as well as in artistic installations. As Dombois shows, many of the phenomena known from seismology can easily be displayed acoustically and identified.^[17] His work Circum Pacific 5.1 is an example of the spatial conversion of sonified earthquake measurement data in which activity occurring in remote parts of the world can be perceived simultaneously. The project furthermore demonstrates the successful combination of scientific research with an artistic concept.

In recent years, the sonification of EEGs in the area of neurology has established itself as an extraordinarily active field of research.^[18] This is primarily due to the complicated structure of an EEG, which typically consists of several data streams. Because its analysis can only be partially automated, a high degree of expertise is required for its interpretation. Here, sonification has the potential to make complex rhythmic structures perceptible. Current research on EEG vocal sonification, in particular, shows promising approaches, as painstaking work has been carried out on the development of a canonic method. One of the goals has been to develop software components for the manufacturers of EEG equipment that enable signal analysis and above all the real-time diagnosis of EEGs during the clinical monitoring of patients.^[19]