Noise reduction IN NOISY AND QUIET ENVIRONMENTS.
The sound that a hearing aid wearer hears is “shaped” by the Hearing Aid Specialist/audiologist, who makes computerized adjustments to the hearing aid program. The type of sound that performs well in a quiet home is not the same as the amplification that is in a noisy car or restaurant.
Manufacturers have greatly improved the “noise-reduction” abilities of their hearing aids, in recent years. However, you need to understand that it is wonderful for some people but not for others. It depends on your type of hearings loss, your hearing aid features, and possible use of an ear mold.
THE HEARING AID LISTENING PROGRAM
Many hearing aids have a button you push to select a particular “listening program.” What is a “listening program”? Well, a good way to understand the concept is by comparing hearing aids to eyeglasses. You are probably familiar with “bifocal” lenses: the top lens is designed for long-distance vision; the bottom lens is designed for close-up work.
Similarly, your hearings aids may have more than one listening program. If that your hearing aids have two listening programs. The first program is designed for normal listening, such as talking to people across a room or listening to television. The second program might be designed for communication in a noisy car, dining room or restaurant. This is a situation where you need to hear the person across the table three feet away, but you do not want to hear all the noise in the room.
The amount of background noise that hearing aids eliminate differs very much from patient to patient and from hearing aid model to hearing aid model. Not all hearing aids have noise-reduction microphones. Also, some patients—for example, people with mild hearing loss—do not benefit very much from noise-reduction technology.
OPEN-FITTED and RIC HEARING AIDS
If you are a hearing aid wearer whose hearing, when unaided, is close to normal in the lower frequencies and has a mild-to-moderate loss in the higher frequencies, you probably wear “open fitted” instruments, without an ear mold.
They are called “open fitted” because they leave the ear canal open. There is no solid plastic part (ear mold) that plugs your ear canal and stops noise from entering. Instead of acting like noise plugs, open-fitted hearing aids allow background noise to go into the ear naturally, without being processed by your hearing aids. That means that you are not going to notice a reduction in background noise when you activate your Program 2. The noise level, either with or without the hearing aids, is going to sound the same.
Most of the background noise is in the lower tones. If your hearing is good in the lower frequencies—that is people that hear the same with or without hearing aids. Activating the noise-reduction system can’t modify the background noise that enters your ear naturally.
PROFOUND HEARING LOSS
If you have a profound hearing loss (i.e., you are unable to hear well without hearing aids), noise-reduction technology is helpful, but not spectacularly so. When the noise-cancellation circuit are fully activated, they may remove so much sound that there isn’t enough left for you to hear well.
So, patients with mild hearing loss and those with profound loss–do not experience as much benefit from noise reduction as people with moderate hearing loss.
MODERATE AND SEVERE HEARING LOSS
If you have moderate hearing loss you may experience huge amounts of noise reduction when you switch from the normal listening program to the noise-reduction program. People with moderate hearing loss are usually fitted with occluding earmolds (plastic that plugs up the ear) that act like effective noise plugs when you use the noise-reduction system.
Remember that this is possible only for people who have moderate (or severe) levels of hearing loss and are wearing occluding ear molds.
PERIODIC Professional adjustment
You may want to have your hearing professional “ADJUST” your hearing aids’ noise-reduction system after you have worn them for some time, to make sure they are helping you as well as possible.. Hearing aid microphone openings often get dirty and lose their ability to eliminate noise and require cleaning.
To test how well your hearing aids’ noise reduction is working, check them in a noisy listening environment, like a noisy restaurant or shopping center. Switch between your normal program and your noise-reduction program. You should hear a significant difference.