Thesis (Ph. D.)--Ohio State University, 2004. / Title from first page of PDF file. Document formatted into pages; contains xii, 136 p. : ill. Advisor: Hilary Apfelstadt, School of Music. Includes bibliographical references (p. 102-107).

Thesis (D. Mus. Arts)--University of Washington, 2004. / Vita. Includes bibliographical references (leaves 87-89).

Thesis--University of Southern California. / Includes bibliographical references.

Thesis (Ph. D)--State University of Iowa, 1963. / Includes bibliographical references (leaves 241-246).

Thesis (Ph. D.)--Royal Holloway College, University of London, 2002. / Includes bibliographical references (p. 341-365).

Thesis (M.M.)--University of Wisconsin-Madison, 1980. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 82-84).

Thesis (Ph. D.)--University of Missouri-Columbia, 2005. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file viewed on (November 8, 2006) Vita. Includes bibliographical references.

Treatise (D.M.A.) Florida State University, 2007. / Advisor: Carolyn Bridger, Florida State University, College of Music. Title and description from dissertation home page (viewed 10-8-2007). Document formatted into pages; contains 68 pages. Includes biographical sketch. Includes bibliographical references.

The field of biological acoustics has witnessed a steady increase in the research into overtone singing, or “throat-singing,” in which a singer utilizes resonance throughout the vocal tract to sing melodies with the overtones created by a vocal drone. Recent research has explored both how a singer vocalizes in order to obtain rich harmonics from a vocal drone, as well as how further manipulations of the vocal apparatus function to filter and amplify selected harmonics. In the field of phonetics, vowel production is quantified by measuring the frequencies of vocal tract resonances, or formants, which a speaker manipulates to voice a particular vowel. Thus, an investigation of throat singing is closely linked to human speech production. Formants are usually detected in vowel spectra obtained using Fast Fourier Transform algorithms (FFTs). An alternative method that provides much higher frequency resolution is external excitation of the vocal tract and measurement of the pressure response signal at the mouth’s opening, which can be used to calculate the acoustic impedance spectrum. We demonstrate the use of such an “acoustic impedance meter” to measure the formant frequencies of common vowels as well as the oscillatory modes of simple resonant pipe systems. The impedance meter accurately measures fundamental pipe modes and a variety of formant frequencies with an uncertainty of 1 Hz. Finally, we assess how the impedance meter may be used to measure the unique resonances achieved by qualified throat singers.

A study was undertaken to identify the effect of head flexion/extension on singing voice quality. The amplitude of the fundamental frequency (F0), and the singing power ratio (SPR), an indirect measure of singer’s formant activity, were measured. F0 and SPR scores at four experimental head positions were compared with the subjects’ scores at their habitual positions. Three vowels and three pitch levels were tested. F0 amplitudes and low frequency partials in general were greater with more extended head positions, while SPR increased with neck flexion. No effect of pitch or vowel was found. Gains in SPR appear to be the result of damping low frequency partials rather than amplifying those in the singer’s formant region. Raising the amplitude of F0 is an important resonance tool for female voices in the high range, and may be of benefit to other voice types in resonance, loudness, and laryngeal function.