Acoustic characterization of the glides /j/ and /w/ in American English

Acoustic analyses were conducted to identify the characteristics that differentiate the glides /j,w/ from adjacent vowels. These analyses were performed on a recorded database of intervocalic glides, produced naturally by two male and two female speakers in controlled vocalic and prosodic contexts. Glides were found to differ significantly from adjacent vowels through RMS amplitude reduction, first formant frequency reduction, open quotient increase, harmonics-to-noise ratio reduction, and fundamental frequency reduction. The acoustic data suggest that glides differ from their cognate high vowels /i,u/ in that the glides are produced with a greater degree of constriction in the vocal tract. The narrower constriction causes an increase in oral pressure, which produces aerodynamic effects on the glottal voicing source. This interaction between the vocal tract filter and its excitation source results in skewing of the glottal waveform, increasing its open quotient and decreasing the amplitude of voicing. A listening experiment with synthetic tokens was performed to isolate and compare the perceptual salience of acoustic cues to the glottal source effects of glides and to the vocal tract configuration itself. Voicing amplitude (representing source effects) and first formant frequency (representing filter configuration) were manipulated in cooperating and conflicting patterns to create percepts of /V#V/ or /V#GV/ sequences, where Vs were high vowels and Gs were their cognate glides.

Department dc:contributor.department

Massachusetts Institute of Technology. Dept. of Electrical Engineering and Computer Science.

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2009

Author dc:creator

• Hunt, Elisabeth Hon

Advisor dc:contributor.advisor

• Kenneth N. Stevens.

• Electrical Engineering and Computer Science.

Statement dc:rights

• M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/1721.1/52797

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/52797