On the development of early vocoders

The historic acoustic-phonetic collection (HAPS) of the Dresden University of Technology [47] preserves historic material from more than 100 years of experimental phonetics in Germany and more than 50 years of speech technology in Dresden. The latter begun with the development of a channel vocoder in the 1950-th which was the starting point for continuous investigations in speech analysis and synthesis. More general, the development of early vocoders had a large impact on speech research in other places also, starting with Dudley's vocoder in the 1930-th. Therefore, this paper will give a survey of the development of early vocoders including some examples for the impacts which they had. Although this study cannot be complete, it gives an impression of pathbreaking work.