Related Experiment Videos
Field-to-microphone transfer functions for completely-in-the-canal (CIC) instruments
1Department of Communicative Disorders, University of Western Ontario, London, Canada.
Ear and Hearing
|August 1, 1997
Summary
This study measured the acoustic advantage of completely-in-the-canal (CIC) hearing devices. Results show CIC microphone placement offers a significant acoustic benefit at different signal directions.
Area of Science:
- Audiology
- Acoustics
- Hearing Aid Technology
Background:
- Completely-in-the-canal (CIC) hearing devices are discreet assistive listening devices.
- Understanding the acoustic properties of CIC devices is crucial for optimizing hearing aid performance.
Purpose of the Study:
- To quantify the field-to-microphone transfer function for standard- and micro-CIC devices.
- To assess these functions at two distinct loudspeaker azimuths (0 and 45 degrees).
Main Methods:
- Field-to-microphone transfer functions were measured in 24 adult participants.
- Custom instrumentation enabled direct connection between CIC microphone output and measurement systems.
- Measurements were taken for standard- and micro-CIC instruments at 0 and 45 degrees azimuth.
Main Results:
- The standard-CIC showed a peak transfer function of 8 dB at 4000 Hz for 0-degree azimuth.
- At 45-degree azimuth, the standard-CIC exhibited a peak transfer function of 13.7 dB at 5000 Hz.
- These findings highlight frequency-dependent acoustic advantages based on azimuth.
Conclusions:
- The study demonstrates a measurable acoustic advantage for CIC microphone placement.
- This advantage is defined across two signal azimuths.
- The findings support the acoustic benefits of CIC devices compared to other hearing aid styles.