Hearing Aid Styles
There are three basic styles of hearing aids. The styles differ by size, their placement on or inside the ear, and the degree to which they amplify sound.
- Behind-the-ear
(BTE) hearing aids consist of a hard plastic case worn
behind the ear and connected to a plastic earmold that fits
inside the outer ear. The electronic parts are held in the
case behind the ear. Sound travels from the hearing aid
through the earmold and into the ear. BTE aids are used by
people of all ages for mild to profound hearing loss.
A new kind of BTE aid is an open-fit, receiver in the canal (RIC) hearing aid. Small, RIC aids fit behind the ear completely, with only a narrow speaker wire inserted into the ear canal, enabling the canal to remain open. For this reason, open-fit hearing aids may be a good choice for people who experience a buildup of earwax, since this type of aid is less likely to be damaged by such substances. In addition, some people may prefer the open-fit hearing aid because their perception of their voice does not sound "plugged up." - In-the-ear (ITE) hearing aids fit completely inside the outer ear and are used for mild to severe hearing loss. The case holding the electronic components is made of hard plastic. Some ITE aids may have certain added features installed, such as a telecoil, a small magnetic coil that makes it easier to hear conversations over the telephone. ITE aids usually are not worn by young children because the casings need to be replaced often as the ear grows.
- Canal aids fit into the
ear canal and are available in two styles. The in-the-canal
(ITC) hearing aid is made to fit the size and shape of a
person's ear canal. A completely-in-canal (CIC) hearing aid
is nearly hidden in the ear canal. Both types are used for
mild to moderately severe hearing loss.
Because they are small, canal aids may be difficult for a person to adjust and remove. In addition, canal aids have less space available for batteries and additional devices, such as a telecoil. They usually are not recommended for young children or for people with severe to profound hearing loss because their reduced size limits their power and volume.
Hearing aids work differently depending on the electronics used. Analog electronics was the former type used however most manufacturers have phased out analog aids. The newer digital aids now offer better clarity and more fine-tuning ability than the older analog aids.
Digital aids convert sound waves into numerical codes, similar to the binary code of a computer, before amplifying them. Because the code also includes information about a sound's pitch or loudness, the aid can be specially programmed to amplify some frequencies more than others. Digital circuitry gives an audiologist more flexibility in adjusting the aid to a user's needs and to certain listening environments. These aids also can be programmed to focus on sounds coming from a specific direction. Digital circuitry can be used in all types of hearing aids.