People with impaired hearing should be thankful to technology for the major improvements that have been made in "hearing aids". It was not too long ago that people with impaired hearing had to live their lives without a hearing aid. It was the transistor technology that heralded the early electronic hearing aids.
The sound amplification unit was the size of a deck of cards that could be carried in the pocket with a cord attached to the speaker that was placed in the ear. Normal AA sized batteries powered the amplification unit, and there was a volume control knob on the unit. This type of hearing aid was worn in one ear.
In the nineteen fifties and sixties, when thick rimmed glasses were in fashion, hearing aids were fitted in the frame of the glasses. However, you could not use one without the other. These did help people who had impaired vision and hearing.
As technology advanced, behind the ear hearing aid became popular. This aid consists of a case, a tube and an ear mold. The case is placed behind the ear and a tube connects it to the ear mold. The sound amplification system is in the case, and the sound is routed through the tube to the ear mold. Sound can be routed either acoustically or electrically. If the sound is routed electrically, the speaker is placed in the ear mold. The ear mold is made from an impression taken of the person's outer ear. This ensures that it fits the ear comfortably. A variety of materials are used in making ear molds, and there is a choice of colors as well.
For people with mild to severe hearing problems, a second type of hearing aid is available that is fitted in the outer ear bowl. These are made to fit the shape of the ear bowl of customers. There used to be a feedback problem in the earlier versions of this device. However, those have now been gotten rid of. The modern day device is made from silicon and does not need to be replaced in growing children.
Another type of hearing aid is called the ear canal device. The device is similar to the behind the ear device and the only difference is that the speaker is placed within the ear canal. This type of hearing aid is the most invisible one and does not block the ear passage.
There are very small in the ear hearing devices, but they are quite expensive, as they are custom-made to fit the ear of each individual. There are other types of hearing devices that are surgically placed inside the ear canal. However, these again are quite expensive. You can also buy disposable hearing devices online. They do not have a battery that can be replaced and they usually work for three to four months. These are typically behind the ear devices.
With advancements in wireless technologies, now there are hearing devices transmit the sound to the ear speaker by wireless. FM systems are used for sound transmission in these hearing devices.
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