THE SIGNIFICANCE OF THE SECOND FORMANT IN SPEECH INTELLIGIBILITY.
Abstract
A new experiment is reported in which contributions of the first and second formants to the intelligibility of clipped speech are measured. The data confirm that the second formant is a major contributor to speech intelligibility. A second formant tracker was designed and built that examines the behavior of the formant in connected speech. It employs a transient approach to analysis of speech signals that contrasts with more generally used Fourier methods. Examination of the outputs for many speakers shows a logarithmic similarity among outputs for the same words enunciated by many speakers. Implications of this finding are discussed. A real-time speech analysis-synthesis apparatus was constructed that uses only second formant information in speech synthesis. Errors in recognizing vowels for 100 words were few (mainly the mistaking of /u/ for /I/). A defect that refinement of second-formant extraction processes will not rectify is inability to synthesize the liquids /l/ and /r/; these were generally classified as the glide /w/. It is suggested that the transient approach to speech analysis should also be applicable to other heavily damped oscillatory signals, periodic or aperiodic. The report also contains an introductory section that reviews current problems in speech analysis and synthesis. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 1966
- Accession Number
- AD0654326
Entities
People
- Ian Bryce Thomas
Organizations
- University of Illinois Urbana–Champaign