HEARING AIDS
Choosing a hearing aid type
Hearing instruments come in a wide variety of types, sizes and options. There is not one hearing instrument that is the “best” or suited to every hearing loss. Selecting a hearing instrument will depend on the degree and shape of the hearing loss, personal preference for size, as well as the listening needs of the wearer. Any limitations the patient may have in manual dexterity and visual acuity will also be factored into the decision process. No two hearing losses are the same and everyone's listening needs are different. The listening needs of one person may include frequent meetings and parties; another may need a hearing aid only for TV.
All hearing instruments amplify sound and have 4 basic components: a microphone to pick up sound, an amplifier to increase and shape the sound, a receiver (or speaker) to deliver the sound to the ear and a battery. There are two main decisions in the initial selection: the type of circuit and the size.
Hearing Aid Types
Hearing instrument circuits are of two general types: analog or digital. In simple terms, analog and digital refer to how the amplifier processes or shapes the sound
Analog or conventional, hearing aids have been in use for over 60 years. The incoming sound wave is enlarged or amplified, making it louder. Some minor adjustments of bass, treble and loudness are available. Analog hearing aids usually require a user-adjusted volume control. One subcategory of analog hearing aids is a programmable hearing aid. A programmable hearing instrument allows the audiologist to make finer adjustments to the amplifier through a computer. Analog hearing aids have a fixed response, amplifying speech and background noise equally.
Digital are today's most advanced technology and have been in use for the past 5 –7 years. The incoming sound wave is broken into very small bites of data. Once the signal is digitized, a microprocessor (computer) chip can apply a mathematical formula to quickly and precisely make millions of changes to the signal each second. Digital hearing aids are able to self-adjust the volume, reduce some unwanted background noise, offer low-battery warning signals and adjust the frequency response in changing listening environments. The fact that a hearing aid is digital does not make it better than a comparative analog hearing aid. But digital hearing aids offer more levels of sophisticated technology, adding greater flexibility, speed and precision to the fitting process. |
