The effect of vowel lengthening on the intelligibility of occluded Lombard speech

Authors

  • Xinyi Zhang ÉTS
  • Meghan Clayards McGil
  • Rachel Bouserhal ÉTS

Abstract

When speaking in noise, people’s vocal effort is automatically adjusted in order to improve the intelligibility of their speech; this phenomenon is called the Lombard effect. However, when the ear canals are blocked by, for example, hearing protection devices or hearables, the occlusion of the ears causes significant changes in speech production, particularly in noise. The result is a Lombard speech that is less intelligible than its typical form; we refer to this as occluded Lombard speech. The change in speech production is due to the lowered noise levels at the ear canals caused by the passive attenuation of the in-ear devices, as well as a change in the talkers’ perception of their own voice.

One main characteristic of the open-ear Lombard speech is elongated vowels; however, this elongation is much shorter in occluded Lombard speech. This discrepancy leads to our research question: Can elongating the vowels in the occluded Lombard speech improve its intelligibility?

To answer this question, thirteen participants, all native French speakers, listened to seventy-eight sentences of occluded Lombard speech from an open-access database. These sentences were presented to the participants under five signal-to-noise ratios (-3 dB, 0 dB, 5 dB, and 10 dB). Among all these stimuli, half of them had their vowels artificially lengthened. Participants were asked to repeat the sentence and then rate the ease of understanding after listening to each sentence. The number of words correctly repeated and the self-rated ease of understanding are analyzed and presented.

 

Additional Files

Published

2022-08-09

How to Cite

1.
Zhang X, Clayards M, Bouserhal R. The effect of vowel lengthening on the intelligibility of occluded Lombard speech. Canadian Acoustics [Internet]. 2022 Aug. 9 [cited 2024 May 2];50(3):86-7. Available from: https://jcaa.caa-aca.ca/index.php/jcaa/article/view/3884

Issue

Vol. 50 No. 3 (2022)

Section

Proceedings of the Acoustics Week in Canada

License

Author Licensing Addendum

This Licensing Addendum ("Addendum") is entered into between the undersigned Author(s) and Canadian Acoustics journal published by the Canadian Acoustical Association (hereinafter referred to as the "Publisher"). The Author(s) and the Publisher agree as follows:

  1. Retained Rights: The Author(s) retain(s) the following rights:

    • The right to reproduce, distribute, and publicly display the Work on the Author's personal website or the website of the Author's institution.
    • The right to use the Work in the Author's teaching activities and presentations.
    • The right to include the Work in a compilation for the Author's personal use, not for sale.

  2. Grant of License: The Author(s) grant(s) to the Publisher a worldwide exclusive license to publish, reproduce, distribute, and display the Work in Canadian Acoustics and any other formats and media deemed appropriate by the Publisher.

  3. Attribution: The Publisher agrees to include proper attribution to the Author(s) in all publications and reproductions of the Work.

  4. No Conflict: This Addendum is intended to be in harmony with, and not in conflict with, the terms and conditions of the original agreement entered into between the Author(s) and the Publisher.

  5. Copyright Clause: Copyright on articles is held by the Author(s). The corresponding Author has the right to grant on behalf of all Authors and does grant on behalf of all Authors, a worldwide exclusive license to the Publisher and its licensees in perpetuity, in all forms, formats, and media (whether known now or created in the future), including but not limited to the rights to publish, reproduce, distribute, display, store, translate, create adaptations, reprints, include within collections, and create summaries, extracts, and/or abstracts of the Contribution.