A synthetic speaker

Abstract This synthetic speaker is an electrical device manipulated by keys and levers for the production of synthetic vocal sounds and their combination into speech. The device was developed as an interesting educational exhibit by the Bell System at the San Francisco Exposition and the New York World's Fair. From a buzzer-like tone and a hissing noise as raw material, the operator skillfully shapes speech by manipulating the controls to give inflection and the sound spectrum that differentiates one speech sound from another. This paper covers the development of the device and the training of the operators to demonstrate it.