Singing synthesis and the Vocal Tract Organ

Vocal synthesis has been the subject of investigation since the late 18th century when von Kempelen produced his mechanical ‘speaking machine’. The advert of electronics has enabled a number of different methods of voice synthesis to be realized in practice. Recently with the advent of 3-D printing and magnetic resonance imaging of human vocal tracts, it has been possible to create synthetic vocal sounds that combine both mechanical (3-D printed tracts) and electronic (synthesized larynx sound source) to enable the effects of various parts of the vocal tract on the acoustic output to be investigated. Given that the 3-D tracts look rather like organ pipes, the author (an organist) has developed a new musical instrument based on this technology, which is called the Vocal Tract Organ. This paper reviews voice synthesis techniques and describes the structure and operation of the Vocal Tract Organ.