Hearing aids are marvels of advanced technology, and they keep improving. Each technological advance delivers more features and functions in a smaller space. One such technology is the directional microphone. Many of today’s hearing aids incorporate this device, allowing the wearer to enjoy a more natural hearing experience.
Older hearing aids relied on omnidirectional microphones to amplify sound. This type of microphone picks up on sounds from all directions equally. When used in a quiet setting (such as in the home), an omnidirectional microphone works quite well, but it is not as effective in noisy environments. In order to compensate for this, directional microphones focus closely on sounds emanating from the front. Users can focus more clearly on what the people in front of them are saying, rather than being distracted by background noise.
Both omnidirectional and directional microphones have advantages, so many hearing aid manufacturers include both types in their products. How you use these microphones varies from device to device. In some cases users can manually switch back and forth between microphones, usually through a small switch. Other devices can pick up on which microphone is most useful in a given situation and will automatically switch back and forth.
A third type of hearing aid microphone is the adaptive directional microphone. This device offers variation in the direction of amplification, automatically picking up on speech signals and focusing in on the direction they are coming from. Adaptive microphones can be troublesome in crowded environments where many speakers are present, but the user can usually switch to a forward only mode in these situations.
Hearing aids designed for kids sometimes utilize directional microphones, but caution is needed when using these devices. Children learn language by hearing the people around them speaking, but a directional microphone can limit a child’s exposure to this incidental speech. Children may also have difficulty hearing traffic with this type of microphone. Parents should be sure that their child’s directional microphone is only turned on in appropriate situations.
Despite its flaws, hearing aids equipped with a directional microphone can greatly increase a person’s ability to hear and interact with the world around him.