There are three main types of hearing aids in use today: behind-the-ear, in-the-ear and completely-in-canal. A brief description follows of the three types and some of the different features available within each type. Behind-the-ear (BTE) hearing aids
Behind-the-ear hearing aids consist of a plastic casing containing the electronics, from which the amplified sound is fed through a clear plastic tube to an earmould. The earhook on the behind-the-ear hearing aid connects to this tube, which itself forms the connection to the custom made earmould worn in the user's ear. It is very important that the ear-mould fits well and is placed correctly in the ear, so the user obtains the best possible performance from the hearing aid and avoids acoustic feed- back (whistling). The tube must also be adjusted to the correct length and be soft and pliable. Volume is adjusted either automatically, or with a manual volume control in the form of a small lever or wheel. Most BTE models also have a "T" switch to select the telecoil mode, for receiving sounds transmitted from an induction loop See Alternative Assistive Listening Devices. On some models, the battery compartment has a built-in on/off switch; on others the on/off function is combined with the "T" switch. Behind-the-ear hearing aids are available in a wide range of types and performance levels. High power hearing aids help people with severe hearing losses. Hearing aids with directional microphones make it easier for the user to hear speech in background noise, as they amplify sound coming from the front of the user more than unwanted sounds coming from behind. Some models are equipped with a remote control for selecting different listening programs in different sound environments, while others accomplish this automatically. In-the-Ear (ITE) Hearing Aids. Unlike behind-the-ear hearing aids, in-the-ear hearing aids are placed inside the ear and consist of only one part (the shell) into which the electronics are built. The shell is custom-made from an impression of the user's ear canal. This type of hearing aid is often 100% automatically controlled, but on some models it is possible to adjust the volume manually by means of a small lever or wheel. The battery compartment on some ITE aids has a built-in on/off switch, and on others the on/off function is combined with the volume control. others the on/off function is combined with the volume control. ITE models can usually be ordered with a "T" switch (space permitting) to select the telecoil mode, for receiving sounds transmitted from an induction loop. Completely-in-Canal (CIC) Hearing Aids are, as the name indicates, placed deeply within the ear canal. Despite the small size, this hearing aid type contains the latest technology of equal quality to larger models. They are almost invisible in the ear, so nobody can see you are wearing hearing aids. The position of CIC aids deeper in the ear canal provides certain natural acoustical advantages. These diminish problems with wind noise, make it easier to speak on the telephone using a normal handset and also help to determine from which direction sounds are coming. The CIC is usually fully automatic and has no space for any additional manual controls. The battery is located in the lid of the CIC, which also functions as its on/off switch. It is not possible to incorporate a telecoil into a CIC model. Although hearing aids cannot restore your original hearing ability, they can make the most of your remaining hearing ability. They may also be your way back to active life, where you do not have to make a constant effort to hear. The latest technology has brought us much closer to the goal of offering total compensation for each individual hearing loss.