Acoustic characteristics of disguised speech

speaker strategies and listener error patterns

Authors

  • Allan B. Smith University of New Hampshire
  • Nealy Mason University of New Hampshire
  • Molly E. Browne University of New Hampshire
  • Brendan Sullivan University of New Hampshire

DOI:

https://doi.org/10.1558/ijsll.38372

Keywords:

speaker identification, voice identification, acoustic cues robust to disguise, disguised speech

Abstract

   

A group of 13 participants were recorded in two conditions: 1) speaking normally and 2) altering speech to conceal their identity (i.e., disguised speech). Participants were not instructed how to disguise their speech because we were interested in which changes they would choose. A group of inexperienced listeners were largely inaccurate in matching participants' disguised speech to their normal speech. The largest changes between normal and disguised speech were in speaking rate, the first formant, fundamental frequency, and intensity. When listeners made correct matches, the pairs were similar in speaking rate and fundamental frequency (F0), as shown by significant correlations. Incorrectly matched pairs were not significantly correlated, suggesting that listeners were not making good use of acoustic cues during those decisions. Overall, the third formant (F3) and speaking rate appeared to be useful acoustic indicators of identity when matching normal and disguised speech samples. Of those two variables, F3 was apparently underutilised by listeners. The implications for what spontaneous speakers do to disguise their speech and what naïve listeners attend to when identifying disguised voice are discussed.

Author Biographies

  • Allan B. Smith, University of New Hampshire

    Allan B. Smith is a Clinical Associate Professor at the University of New Hampshire, USA, where he teaches phonetics and speech/hearing science. He earned his Master's degree in Speech-Language Pathology at Massachusetts General Hospital Institute of Health Professions and his PhD in Communication Science at the University of Connecticut. His primary area of research is acoustic measurement of speech in children with speech, language, and reading disorders.

  • Nealy Mason, University of New Hampshire

    Nealy Mason is a graduate of the University of New Hampshire where she earned a BS in Communication Sciences and Disorders. She will be attending graduate school with a major in Speech-Language Pathology.

  • Molly E. Browne, University of New Hampshire

    Molly Browne graduated from the University of New Hampshire with a BS in Communication Sciences and Disorders. She works as a speech-language pathologist assistant at a clinic for children with autism. She plans to pursue her Master's in Speech-Language Pathology.

  • Brendan Sullivan, University of New Hampshire

    Brendan Sullivan will be attending the University of Connecticut where he will study speech-language pathology. He earned a BS in Communication Sciences and Disorders at the University of New Hampshire, USA.

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Published

2019-09-11

Issue

Vol. 26 No. 1 (2019)

Section

Articles

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© Equinox Publishing Ltd.

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How to Cite

Smith, A. B., Mason, N., Browne, M. E., & Sullivan, B. (2019). Acoustic characteristics of disguised speech: speaker strategies and listener error patterns. International Journal of Speech, Language and the Law, 26(1), 85-95. https://doi.org/10.1558/ijsll.38372