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hearing aid technologies

Hearing Aid Technology

We live in a digital world—and hearing instruments are no exception. Not
only does digital signal processing result in more accurate hearing, it can be adjusted to individual needs in a way older analog hearing instruments never could.

Digital signal processing has brought tremendous advances in hearing health. New technologies can improve sound clarity and speech intelligibility, reduce noise, and
even connect you with wireless devices like cell phones, TVs and MP3 players. Most importantly, digital hearing aids are custom programmed so they can be “fine tuned”
to your personal hearing needs.

Here are some of the many technologies digital hearing instruments may offer:

Technology What it does 

Digital Signal Processing

Converts the incoming sound into digital values for processing, then converts them back into sound pressure waves that stimulate your auditory system. Processing a signal digitally allows the hearing aid to enhance the original sounds to improve the sound quality and helps reduce noise and feedback (whistling).

Automatic Gain


Automatically changes how much sounds at different frequencies are amplified. This is very individual, as the range of frequencies you can hear will be different from other people. AGC helps make softer speech sounds audible while controlling how much unwanted loud sounds are amplified.

Noise Reduction

Reduces annoying noise that can get in the way of conversational speech. This is done by analyzing the incoming sound and separating speech from steady background noises (like a refrigerator or fan). The speech is amplified and the noise is decreased to provide comfort and better speech understanding.

Noise Reduction

Reduces sudden, loud sounds like the clinking of silverware or jangling of keys, without modifying other sounds that may contain important speech cues.

Soft Noise Reduction

Keeps soft sounds quiet by providing less amplification for sounds that are quieter than conversational speech. This improves the quality of sound from the hearing device when worn in quiet situations.

Noise Reduction

Prevents noise caused by wind from being over amplified. This improves the quality of amplified sound in outdoor environments.

Adaptive Feedback Cancellation

Detects sudden feedback (whistling or squeal) in a hearing device then removes it by applying a cancelling signal. If the cause of the feedback changes, the cancelling signal will automatically adapt. Adaptive Feedback Cancellers are designed to manage transitory feedback (e.g. feedback that happens when you place a hand or telephone next to your ear). This doesn’t resolve on-going feedback, which might be due to a poorly fitted earmold or hearing device.

Omni Microphone

Emphasizes sounds equally from all directions. All hearing devices have omni microphone capability.


Emphasizes sounds coming from the front; de-emphasize sounds coming from the sides and behind. Since most conversations occur when you’re facing a speaker, directional microphones help you focus on that source. Directional technology is available on all but the very smallest custom models which are limited by size constraints.

Automatic Directional

Allows a hearing device to automatically switch from an omni microphone setting to a directional microphone setting when the system predicts better performance with the directional settings.

Adaptive Directional

Allows the hearing device to dynamically change directional settings to provide maximum reduction towards the location of the dominant noise source.

Listening Memory/

Provides settings designed for a particular listening situation. Most hearing devices have two to four listening memories/ programs (e.g. listening in noise, telephone use, etc). Changing programs or memories is done by pressing a button on the hearing device or with a remote control. Some hearing devices have a "Universal" listening memory that works well in a variety of situations and automatically adapts without having to push a button. Multiple listening memories are not available in some smaller models due to space limitations.


This broad term can refer to many different features: communication between hearing devices ('binaural coordination'), communication between hearing devices and external audio sources (e.g. mobile phones, TVs, etc.), the ability to control devices remotely ('remote control'), and the ability for hearing care professionals to program devices without wires. Wireless connectivity features are available for select products and models.

Open Fit

A style designed to keep the ear canal as open as possible to prevent the occluded - or 'stuffed up' - feeling associated with wearing a hearing device. This can be done with large vents (e.g. custom devices or earmolds for behind-the-ear style instruments) or by moving the majority of the hearing device components behind the ear, leaving the ear canal as open as possible (e.g. thin tube behind-the-ear or receiver-in-the-canal style devices). This style is well suited for those with Mild to Moderate hearing loss.


Transmits electromagnetic signals from the handset of a telephone to the hearing device. Because the sound is transmitted as an electromagnetic signal, telecoils can help prevent feedback. Telecoils are not available in some smaller models due to space limitations.

Volume Control

Allows you to adjust the volume manually using a control on the hearing aid. Volume controls are not available on some smaller models due to space limitations.

Remote Control

Allows you to adjust the volume and memory/program selection without touching the hearing device. Remote controls are available for select products and models.

Digital hearing aids
Understand how today's technologies work.