HK Hearing & Speech Centre

Hearing Aids Glossary

Hearing Aids Glossary was prepared by HK Hearing & Speech Centre ( to help all ages with hearing issues to easily understand our hearing services including hearing test (audiological assessment) evaluation, hearing aids prescription (hearing aid consultation, recommendation and fitting), hearing rehabilitation, hearing aid products & hearing aid accessories, custom earmolds, and relevant professional hearing counseling services. We tried to gathered some common terms related to hearing aids and explain them in common language. For further assistance, please contact us.Hearing Aids Glossary

Hearing Aids Glossary is listed in alphabetical order.

Adaptability is the ability of the hearing aid to change its’ settings based on the listening environment.

Algorithm is the procedure or formula that a digital processor uses to calculate what needs to be done with sound as it goes through the hearing aid.

Amplifier is an electronic component that increases the loudness of sound so that the hearing aid user can hear.

Analog hearing aid
Analog hearing aid is the basic hearing aid that amplifies sound based on your audiogram. The signal amplification is done without manipulating to deal with environmental noise.

Asymmetrical hearing loss
Asymmetrical hearing loss is the degree of hearing loss in one ear that is greater than the other.

Audibility is the level at which a sound can be heard.

Audiometer is the basic hearing test equipment used to perform a hearing test.

Audiogram is a chart used to plot an individuals scores from a hearing test.

Automatic volume control
Automatic volume control means the hearing aid can automatically adjust the volume for the user.

Automatic gain control
Automatic gain control (on most hearing aids) is a component that automatically limits the maximum volume so the amplification will not be too much to cause inconvenience.

Age-related hearing loss (presbyacusis)
It is a sensorineural hearing loss and occurs symmetrically on both ears. This will cause a degradation in speech understanding and issues on handling loud noises.

Battery is the power source for a hearing aid.

Behind the Ear Hearing Aid (BTE)
It is style of hearing aid in which the components are placed behind the ear and the sound is delivered to the ear through a tube connect to an ear mold.

Bilateral hearing loss
Bilateral hearing loss is a hearing loss in both ears.

It is earwax.

Completely In Canal Hearing Aid (CIC)
It is the smallest style of hearing aid in which all or nearly all of the hearing aid is placed inside the ear canal.

Cochlea is a small snail shaped organ in which sound is processed and then sent to the brain.

Conductive hearing loss
Conductive hearing loss is a hearing loss due to damage to the conductive portion of the auditory system such as the eardrum or the bones in the middle ear. It is possibly caused by ear wax plug, a result of lack of parts of the outer ear, missing or damaged hearing bone or some structural issue in the hearing canal. It can also be due to a damaged ear drum or fluid accumulation behind the ear drum. Conductive hearing loss is typically reversible. If not, on many cases, there is medical treatment to improve the situation.

Combined hearing loss
Combined hearing loss is a hearing loss that combines a conductive hearing loss with a sensorineural hearing loss.

Dead ear
Dead ear means no response on all frequencies. It is deafness.

Deaf means a person that is not able to perceive sound and / or understand speech even when the sound is amplified.

Decibel (dB)
Decibel (dB) is a measurement of the loudness of a sound.

Digital hearing aid
Digital hearing aids provide an advanced way to handling noise filtering.

Digital speech enhancement
Digital speech enhancement is the enhancement of speech signals by a digital processor to make speech more readily distinguished from noise.

Disposable Hearing Aid
Disposable Hearing Aid is a hearing aid designed to be worn and then thrown away when the battery is used up.

Earmold is the part typically made of silicon and located in the ear on BTE hearing aid. It conducts the sounds from the hearing aid to the hearing canal. Ear mold does not perform any amplification.

Filter (Audio)
In hearing aids, it enables you to amplify certain frequencies and filter the other frequencies so they would not be amplified so that the hearing aid wearer can hear sound in its natural form.

Hearing aid
Hearing aid is an electronic device used to improve damaged hearing.

Hearing aids cleaning
Hearing aid is a delicate digital device exposed to sweat, ear wax, etc. Therefore, cleaning the hearing aid regularly is essential.

Hearing loss
It is a decrease in the ear’s sensitivity to sounds. A person with hearing loss requires higher volume in order to hear well comparing to a person with no hearing loss.

Hearing test
Hearing test is performed in room sealed to noises. The technician plays series of sounds and words on different frequencies and different volume levels in order to define the patient hearing level.

High tone loss
High tone loss refers to hearing loss on higher frequencies.

ITE (In The Ear)
A hearing aid that seats inside the outer ear and fills the pinna.

ITC (In The Canal)
A hearing aid that is placed in the canal. Its outer part can be seen on the entry of the canal.

Localization is the ability to tell where the sounds are coming from. It is based on the differences between our two ears’ hearing as the time and volume the two ears hear is slightly different. This is why bilateral hearing is so important and you have to overcome hearing loss in both ears. Moreover, it is a reason to have a hearing aid for one ear even if the other ear is perfectly OK.

Masking is a situation where louder voices cover quite voices preventing us from hearing it. On some hearing loss types, loud voices from a certain frequency run over voices from other frequencies and hence influences your speech understanding. Another ‘masking’ is performed on hearing test to prevent one ear with masking to help the other ear.

MCI (Most Comfortable Level)
MCI (Most Comfortable Level) is the sound volume that a certain person feels most comfortable. It’s a subjective parameter and it is very individual.

Microphone is a component that receives the sounds and voices from the surrounding and turns it to electrical signals with the right frequency and amplitude.

Open Ear Hearing Aid
Open Ear Hearing Aid is a hearing aid designed to fit over the ear with a thin tube or wire running into the ear, and a small, soft plastic tip. The tip has holes to keep from blocking the ear canal so that the user does not feel plugged. Open Ear hearing aids are primarily used for high frequency hearing loss.

Open fit
It is a hearing aid with ventilation tunnel that goes through it. It allows low tones to pass through it. On the other hand, it amplifies the middle and high frequencies. Great for a high-tone-loss hearing impairment since it enables a more natural hearing without occlusion.

Recruitment is a phenomena that a person with hearing loss feels that voices are louder than how they are perceived by a hearing person. The consequences is that the hearing range of a person with hearing loss is smaller comparing to a fully hearing person.

Sensorineural hearing loss
Sensorineural hearing loss is a hearing loss characterized by a damage to the inner ear or to the hearing nerve. This kind of hearing loss not only causing a higher hearing threshold but also harms the ability to distinguish between sounds. The cause can be age, noise, ototoxic medicine, hearing nerve tumor, congenital deafness and other diseases. Sensorineural hearing loss is usually not fixable.

Stable hearing loss
Stable hearing loss is a hearing loss that has not changed for several years.

HK Hearing & Speech Centre
Rm 02, 5/F., Kai Seng Commerical Centre,
4-6 Hankow Road, TST Kln, HK
(near Kowloon Hotel)
Tel: (852) 3100 0555
Fax: (852) 3100 0556