Automatic Signal Processing
Hearing instruments can monitor your environment and automatically adjust the volume to make speech audible and reduce background noise. Soft sounds are amplified and loud sounds receive
little or no amplification. This type of signal processing keeps the output of the hearing instrument comfortable, so manual changes are unnecessary.
Feedback is the whistling or buzzing noise that a hearing aid can make. Feedback management
technology allows hearing aid users access to increased high frequency amplification without
feedback. High frequency information carries the sounds of speech responsible for clarity. It is
possible to reduce feedback by reducing the volume, though this can affect the clarity of speech.
Modern feedback cancellation methods continually monitor the incoming signal and adjust the
hearing instrument to minimize feedback without reducing gain.
The inability to hear amidst background noise (in a restaurant or at a party) is a common complaint among people with hearing loss. Modern hearing instruments are able to continually monitor the incoming signals and determine the amount of noise in the environment. They then automatically minimize background noise. This allows the user to listen to speech more comfortably and clearly in noisy environments.
Another type of technology that improves speech understanding in noisy environments is the use of directional microphones. Most directional microphone systems help focus on the sounds of interest coming from the front by reducing amplification from the sides and back of the user. The most current directional microphone systems automatically reduce the noise source in the environment.
Multiple Listening Programs
This feature allows the hearing instrument user to change listening programs depending on their environment. For example, hearing instruments can be set with programs for everyday listening, listening in noise, or when using the telephone.
A telecoil attempts to eliminate the feedback or whistling that occurs while wearing a hearing instrument and using a telephone. This feature will only amplify telephone signals from hearing compatible phones. This feature can be accessed automatically when a telephone is placed near the hearing aid or manually by pressing a program button.
Direct Audio Input
Direct Audio Input allows a hearing instrument to communicate with assistive listening devices. It is often used in classrooms and auditoriums to assist in hearing performance. Direct Audio Input is typically available on BTE hearing instruments.