J Am Acad Audiol 2017; 28(01): 103-104
DOI: 10.3766/jaaa.281ceu
JAAA CEU Program
Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

JAAA CEU Program

Volume 28, Number 1 (January 2017)
Further Information

Publication History

Publication Date:
26 June 2020 (online)

Questions refer to Korhonen et al, “Evaluation of a Wind Noise Attenuation Algorithm on Subjective Annoyance and Speech-in-Wind Performance,” 46–57.

Learner Outcomes:

Readers of this article should be able to:

  • Identify the style of hearing aid that experiences the greatest amount of wind noise.

  • Explain how least-mean-squares filtering can reduce uncorrelated noise, serving as the basis for hearing aid wind noise attenuation.

  1. Wind noise in hearing aids is generated when:

    • wind passes objects (trees, shrubs, car window) in the listening environment and creates noise

    • wind generates turbulences at the hearing aid microphone membrane

    • hearing aids generate internal circuit noise

  2. Because of its microphone placement, completely-in-the-canal and in-the-canal devices generally:

    • experience less wind noise than BTE devices

    • experience more wind noise than BTE devices

    • are immune to wind noise

  3. Generally, the strongest wind noise level is experienced for wind originating from the:

    • front

    • back

    • side

  4. Wind noise attenuation (WNA) algorithms typically use _______ to detect wind noise.

    • anemometer sensors

    • quick changes in the input signal

    • correlation of input signals between front and back microphones

  5. The adaptive WNA algorithm in the current study was designed to remove:

    • uncorrelated noise

    • correlated noise

    • both correlated and uncorrelated noise

  6. Stimuli were prerecorded in a wind tunnel and presented via insert earphones to allow:

    • control of wind characteristics across hearing aid processing conditions

    • post processing with experimental algorithms

    • presenting the stimuli at more comfortable levels

  7. The wind noise levels measured at the output of the hearing aid ranged from:

    • 81 to 109 dB SPL

    • 91 to 119 dB SPL

    • 101 to 129 dB SPL

  8. The measured signal-to-noise benefit at 50% performance level when using the WNA algorithm was ___ dB when wind originated from 0° at 5 m/sec.

    • 2.39

    • 4.39

    • 8.39

  9. Greatest change in annoyance when using the WNA algorithm was reported at a wind speed of:

    • 4 m/sec

    • 6 m/sec

    • 10 m/sec

  10. The phenomenon “apparent wind” refers to:

    • subjective perception of wind severity

    • average wind experienced throughout the day

    • the vector sum of true wind and headwind experienced in still air due to physical movement