What is Hearing Aid Circuitry?
Electronic devices like hearing aids have a variety of electronic parts and complex microchips inside that make them function. Your audiologist will help decide which types of electrical features you need to have in your hearing aid, based on your listening needs, budget and the style of hearing instrument.
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Volume Controls
let you manually adjust how loud things sound. Many hearing aids can control loudness automatically, but sometimes a manual control is desired.
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Telecoils
can improve understanding when used with hearing aid compatible telephones, in theaters, at airports and train stations, at places of worship and other places with hearing aid compatible public address systems.
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Feedback Controls
automatically ensure that the hearing aid doesn’t whistle or squeal while you move your jaw or hold something near your ear.
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Bluetooth Connectivity
allows a hearing aid to pick up wireless signals from Bluetooth equipment. Bluetooth is a wireless signal from digital equipment like a cell phone, computer, personal stereo, car navigation system, remote microphone, or adapters for TVs or land line phones. A Bluetooth phone call can be heard in both hearing aids when using a Bluetooth streamer. Sending the digital sound through your hearing aids instead of regular earbuds provides far better sound quality customized for individual listening needs.
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Noise Reduction Circuitry
reduces interference from loud, background noise. There are many ways that hearing aid circuits can do this. Some hearing instruments filter out background noise better and faster than others.
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Directional Microphones
help you know where sounds are coming from and can follow the main voice as the speaker moves around in noisy situations. This improves speech understanding in noisy places.
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Frequency Transposition
helps people with severe hearing loss for high pitches to access these sounds even when the high pitch nerve cells in the ear are unable to function. This greatly improves speech understanding by allowing you to hear the soft, high pitched consonants that give speech its clarity. It also improves speech understanding in noisy places.
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Memory Buttons or Program Controls
provide manual adjustments for various situations. They make the hearing instrument process sound differently when using telephones or assistive listening devices. They can also make the aid manage sound differently in noisy places than in quiet situations. Some hearing aids can do this automatically, while others use a manual switch.
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Direct Audio Input
connections allow you to plug assistive listening devices directly into a hearing aid. Examples include cords that plug into personal stereos, TVs, computers or lapel microphones. These connections are much less costly than wireless connections for FM or Bluetooth systems.
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Remote Controls
allow users to operate the volume or program controls without touching the hearing aid itself.
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FM Connectivity
allows a hearing aid to pick up wireless signals from an FM transmitter. FM systems use special radio frequency transmitters and receivers to let listeners pick up voices over a long distance. FM systems maximize clarity and reduce the negative affects of noise, echo and distance.
Several standard types of controls built into hearing aids help the audiologist fine tune loudness and sound quality:
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Tone Controls
are used to strengthen or reduce the loudness of sound in certain pitch ranges.
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Maximum Power Output
controls set the loudest levels of amplification.
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Gain Controls
are used to adjust average loudness.
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Automatic Gain Controls
reduce distortion from loud sounds. They keep listeners comfortable when sounds are loud, while still providing amplification for soft sounds.
