Behind the ear aids – Hearing Aid Centre (HAC)
Hearing Aid Centre (HAC) Behind the ear aids are also called “receiver-in-the-aid” or RITA devices. These devices are useful for people who require significant amplification across many frequencies due to moderate to severe hearing loss. Larger models tend to be easier to handle for changing batteries or configuring controls. The ear molds on these are easier to clean than other sorts of devices, but they also will be more visible and prone to buildup of wax. If the ear mold is not vented then that can make the ear feel plugged.
Hearing Aid Centre (HAC) Behind the ear aids (BTE) consist of a case, an ear mold or dome and a connection between them. The case contains the electronics, controls, battery, microphone(s) and often the loudspeaker. Generally, the case sits behind the pinna with the connection from the case coming down the front into the ear. The sound from the instrument can be routed acoustically or electrically to the ear. If the sound is routed electrically, the speaker (receiver) is located in the ear mold or an open-fit dome, while acoustically coupled instruments use a plastic tube to deliver the sound from the case’s loudspeaker to the ear mold. BTEs are also easily connected to assistive listening devices, such as FM systems, to directly integrate sound sources with the instrument. BTE aids are commonly worn by children who need a durable type of hearing aid.
Mini BTE (or on-the-ear) aids – Hearing Aid Centre (HAC)
Hearing Aid Centre (HAC) A new type of BTE aid called the mini BTE (or “on-the-ear”) aid. It also fits behind/on the ear, but is smaller. A very thin, almost invisible tube is used to connect the aid to the ear canal. Mini BTEs may have a comfortable ear piece for insertion (“open fit”), but may also use a traditional ear mold. Mini BTEs allow not only reduced occlusion or “plugged up” sensations in the ear canal, but also increase comfort, reduce feedback and address cosmetic concerns for many users.
Receiver in the canal/ear (CRT/RIC/RITE) – Hearing Aid Centre (HAC)
Hearing Aid Centre (HAC) In a “receiver in the canal” device, the receiver is the speaker which sends sound into the ear. To fit this device may have either a custom-made mold or a general use dome fitting. Many users find this device to be more comfortable. The larger versions are easier to wear. Disadvantages are that these need to be replaced more often due to moisture and wax damage. Also they have technical limits on how much low frequency amplification they can do.
BTE Cross System – Hearing Aid Centre (HAC)
Hearing Aid Centre (HAC) Cross systems are used for people with hearing loss in one ear or significantly more in one ear, this system allows the user to wear technically a microphone in one ear and the speech is transferred into a speaker in the good ear, whilst the cone in the good ear allow normal hearing.
BTE Bi Cross System – Hearing Aid Centre (HAC)
Hearing Aid Centre (HAC) BTE Bi Cross System is the same as the Cross system, however it can also enhance the hearing in the individuals better ear by enhancing the volume of the input, therefore channeling the sound into the good ear, whilst enhancing the clarity and volume for it also
Ear molds – Hearing Aid Centre (HAC)
Hearing Aid Centre (HAC) An ear mold is created from an impression taken of the individual’s outer ear. This usually ensures a comfortable fit and reduces the possibility of feedback. Ear molds are made from a variety of hard (firm) and soft (pliable) materials. The color of the case and ear mold of a BTE aid can be modified and optional decorations can be added.
In the ear aids – Hearing Aid Centre (HAC)
Hearing Aid Centre (HAC) In the ear aids (ITE) devices fit in the outer ear bowl (called the concha). Being larger, these are easier to insert and can hold extra features. They are sometimes visible when standing face to face with someone. ITE hearing aids are custom made to fit each individual’s ear. They can be used in mild to some severe hearing losses. Feedback, a squealing/whistling caused by sound (particularly high frequency sound) leaking and being amplified again, may be a problem for severe hearing losses. Some modern circuits are able to provide feedback regulation or cancellation to assist with this. Venting may also cause feedback. A vent is a tube primarily placed to offer pressure equalization. However, different vent styles and sizes can be used to influence and prevent feedback. Traditionally, ITEs have not been recommended for young children because their fit could not be as easily modified as the ear mold for a BTE, and thus the aid had to be replaced frequently as the child grew. However, there are new ITEs made from a silicone type material that mitigates the need for costly replacements. ITE hearing aids can be connected wirelessly to FM systems, for instance with a body-worn FM receiver with induction neck-loop which transmits the audio signal from the FM transmitter inductively to the tele coil inside the hearing instrument.
Hearing Aid Centre (HAC) Mini in canal (MIC) or completely in canal (CIC) aids are generally not visible unless the viewer looks directly into the wearer’s ear. These aids are intended for mild to moderately severe losses. CICs are usually not recommended for people with good low-frequency hearing, as the occlusion effect is much more noticeable. Completely-in-the-canal hearing aids fit tightly deep in the ear. It barely visible. Being small, it will not have a directional microphone, and its small batteries will have a short life, and the batteries and controls may be difficult to manage. Its position in the ear prevents wind noise and makes it easier to use phones without feedback. In-the-canal hearing aids are placed deep in the ear canal. They are barely visible. Larger versions of these can have directional microphones. Being in the canal, they are less likely to cause a plugged feeling. These models are easier to manipulate than the smaller completely in-the-canal models but still have the drawbacks of being rather small.
In-the-ear hearing aids are typically more expensive than behind-the-ear counterparts of equal functionality, because they are custom fitted to the patient’s ear. In fitting, an audiologist takes a physical impression (mold) of the ear. The mold is scanned by a specialized CAD system, resulting in a 3D model of the outer ear. During modeling, the venting tube is inserted. The digitally modeled shell is printed using a rapid prototyping technique such as stereo lithography. Finally, the aid is assembled and shipped to the audiologist after a quality check.