Acoustic tube models of the human vocal tract for the university classroom

• Published in: European journal of physics Vol. 41; no. 6; pp. 65804 - 65822
• Main Authors: Hirth, Michael, Urbassek, Herbert M, Müller, Andreas, Kuhn, Jochen
• Format: Journal Article
• Language: English
• Published: IOP Publishing 01.11.2020
• Subjects: 3D print; acoustic tube model; vocal tract; vowels
• ISSN: 0143-0807; 1361-6404
• DOI: 10.1088/1361-6404/aba5c8

Composite vessels of cylindrical tubes are often used to provide simple models of vowel formation in the human vocal tract. Already a two-tube model allows one to discuss vowel formation in the context of tube eigenmodes. In order to validate the two-tube model we use 3D printing to build a set of two single tubes and 26 two-tube composites representing different model realizations of the vocal tract. Good agreement between theory and experiment is obtained if the so-called acoustical end correction is taken into account. A better representation of human vowels requires an extension to more than two tubes; thus we took data for the construction from literature and investigate the spectra of five eight-tube models corresponding to the vowels [a:], [e:], [i:], [o:] and [u:]. The experimental work connected with the contextual applications in voice production aims to broaden the student's conceptual understanding of tube resonances depending on the geometry in a more general manner.