Audible circuit noise in hearing aid amplifiers

Area of Science:

• Audiology
• Acoustics
• Electrical Engineering

Background:

• Internal circuit noise in hearing aids can negatively impact user experience, leading to distraction, irritation, and potential rejection of the device.
• Understanding the audibility and objectionability thresholds of this noise is crucial for hearing aid specification, fitting, and design.

Purpose of the Study:

• To determine the acoustic and electrical levels at which internally generated hearing aid circuit noise becomes audible and objectionable.
• To provide data for hearing aid manufacturers and audiologists for improved device design and patient fitting.

Main Methods:

• Simulated internally generated hearing aid circuit noise using an amplifier with no acoustic input and a hearing aid receiver output.
• Tested eight subjects with high-frequency hearing loss to assess perceived noise levels.

Main Results:

• Established the acoustic thresholds for audibility and objectionability of internal circuit noise.
• Established the electrical thresholds for audibility and objectionability of internal circuit noise.

Conclusions:

• The study provides critical data on the audibility and objectionability of hearing aid circuit noise.
• This information can guide the development of hearing aids with reduced internal noise and improved user satisfaction.