Noise background when using a hearing aid. The microphone effect is an acoustic feedback effect. Why do hearing aids whistle? Hearing aid whistling in ear

WHAT ARE HEARING AIDS?

All hearing aids can be classified according to the following features:

• in appearance:
• behind the ear (located behind the ear) - miniature, designed for minimal to severe hearing loss,
• and regular size, suitable for any hearing loss,
• intra-ear (located partly in the external auditory canal, partly in the auricle), compensate for hearing loss from slight to severe (up to 80 dB);
• intracanal or so-called. deep immersion devices, almost invisible (located completely in the external auditory canal) are designed for mild to moderate hearing loss - (up to 60-70 dB);
• by setting method:
• TRIMMER - settings are adjusted with a screwdriver,
• PROGRAMMABLE - information about the settings is entered into the hearing aid using a special programmer via a computer;
• in terms of sound processing
• ANALOG (conventional),
• DIGITAL

Both analog hearing aids and those with digital sound processing can be trimmed and programmable, i.e. settings can be entered into the device manually or using a programmer via a computer.

• in terms of power - the hearing aid must exactly match the degree of hearing loss and never exceed the required amplification. All devices are divided into:
• LOW POWER - designed for hearing loss from slight to moderate, which corresponds to 1-2 degrees (up to 60-70 dB),
• MEDIUM POWER - designed for the degree of hearing loss from moderate to severe (2-3 degree - from 40 to 80 dB),
• POWERFUL - designed mainly for severe hearing loss (3-4 degree - from 60 to 95 dB),
• SUPER POWERFUL - HEARING AIDS, designed to compensate for severe and profound hearing loss (grade 4 - deafness with residual hearing - from 70 to 110 dB).
• sound processing capabilities
• so-called devices BASIC LEVEL OF PROSTHETICS. These include digital and analog hearing aids that have one or two independent tuning channels, LINEAR or NON-LINEAR GAIN, but with a limited number of adjustment options and manual volume control. If the patient has a satisfactory SPEECH INTELLIGIBILITY, these devices provide a fairly comfortable perception of surrounding sounds in silence.
• PROSTHETIC COMFORT LEVEL hearing aids are hearing aids with digital sound processing, non-linear amplification, independent bass and treble adjustment, and automatic volume control. Provide more comfortable listening to ambient sounds in silence due to a sufficient number of tuning options, the presence of a system for suppressing the microphone's own noise, extended dynamic range and very low non-linear distortion.
• HIGH-LEVEL PROSTHETIC devices - this group includes digital hearing aids with high tuning flexibility due to the presence of 3 or more independent channels, special digital algorithms for automatic adjustment in different acoustic situations, with suppression of ambient noise in order to improve speech intelligibility.

The hearing aid amplifies ambient Sounds and transmits them to the internal structures of the ear.

Hearing aid whistles(a high-frequency whistle appears) when amplified Sound enters the Hearing Aid microphone, i.e. when the sounds begin forcibly pushed out. The main task is sealing ear canal and prevent the amplified Sound from escaping to the outside.

When the Hearing Aid is turned on (before it is installed in the ear), a whistle occurs, which indicates that the device is working. After you have put the device on your ear, whistling occurs only in cases when the earmould is incorrectly fitted or not firmly inserted into the ear canal.

There may be several reasons for this situation:

1. Excessive amount of wax in the ear canal.

Which leads to a violation of the normal passage of the amplified Sound.

Ears need to be cleaned periodically.

2. Turn on the Hearing Aid at full volume.

Turn down the volume of your Hearing Aid or contact your Hearing Aid Professional for advice on the need for a more powerful hearing aid for you.

3. Change in body position.

4. Wrong standard or custom earmould.

Contact the Hearing Care Center for a quality custom earmould.

Major Hearing Loss or Hearing Aid Amplification requires an accurate fit of the earmold.

5. Worn out plastic straw that connects the behind-the-ear hearing aid to the earmold.

She pulls out the earmold of the Hearing Aid so that it no longer sits tightly in the ear.

The tubing needs to be replaced periodically.

In modern expensive models of hearing aids, the problem of feedback (whistling) has been successfully solved.

A special feedback suppression function allows you to perform any action without worrying about disturbing Sound.

According to a number of researchers, background noise room ranges from 30 dB in a quiet room to 60 dB in public buildings (G. L. Navyazhsky, S. P. Alekseev, L. S. Godin, R. N. Gurvich, S. I. Murovannaya). Individual noise signals in rooms sometimes reach significantly higher values. Excessive amplification of these noises by the hearing aid causes discomfort to the patient.

There are a number of regularities between amplification external noise hearing aid and speech intelligibility when using it. As noted above, satisfactory speech intelligibility corresponds to an articulation of at least 75%. According to S. N. Rzhevkin, 70% articulation can be achieved when the speech intensity level exceeds the audibility threshold by 30 dB. If we take into account that the intensity of spoken speech is 50-60 dB, and the general noise background of residential and office premises is quite significant, reaching 30-60 dB, it becomes obvious that with the distance of the source of speech, the masking effect of external noise increases.
It reduces speech intelligibility, and a simple increase in the amplification of the hearing aid does not improve the conditions for using it (V. F. Shturbin).

Licklider and Miller established a relationship between speech masking and noise intensity as the ratio of average speech power to average noise power. According to them, for the majority of noise encountered in practical conditions, satisfactory speech intelligibility will be ensured if this ratio exceeds 6 dB.

Kuzniarz indicates that if the speech level exceeds the noise by 10 dB, a complete understanding of odisyllabic words is achieved, and complete masking of speech is observed when the noise level prevails over speech by 10 dB.

In addition to these reasons, hearing aid amplification limited by the possible occurrence of a microphone effect (acoustic feedback). So, R. F. Vaskov and A. I. Chebotarev note that even when using carefully made individual ear plugs, the gain is limited to the level of 70 dB, since acoustic feedback appears at a higher gain.

Special conditions hearing aid use are created with hearing loss with a pronounced loudness increase phenomenon. In such patients, when strong sounds are amplified by the hearing aid, their volume may increase excessively, which will cause discomfort in the ear. Under these conditions, it is advisable to limit the gain (compression), when weak sounds are amplified to a greater extent, and strong sounds to a lesser extent, which will create an equalization of the output signal and protect the patient from the unpleasant influence of strong sounds.

This method allows use more powerful hearing aids for severe hearing loss (M. M. Ephrussi, Rebattu, Morgon).

At major hearing loss accompanied by a significant decrease in the dynamic range of auditory perception (up to 15 dB on average), the dynamic range of speech, equal to 40-50 dB, in some cases significantly exceeds it. M. M. Ephrussi points out that only by compressing the range of sound levels transmitted by the hearing aid, it is possible to ensure the perception of speech without pain, if the output level of the hearing aid does not reach the threshold of unpleasant sensations.

Fletcher and Gemelli found that cutting off sections of speech frequencies with high peak amplitudes has little effect on speech intelligibility, only reducing its naturalness.

in hearing aids set automatic gain control (AGC), which maintains the required predetermined intensity of the output signal, regardless of fluctuations in the level of external sound (R. F. Vaskov, A. I. Chebotarev, A. S. Tokman, B. D. Tsireshkin, Dupon-Jersen ). However, the authors note that the use of AGC can also introduce additional distortions, masking the useful signal more than with simple amplification due to amplification of external noise, since weak signals, which include ambient noise, are amplified in this case to a greater extent.

The main cause of hearing aid beeping is the device does not fit snugly to the ear. Typically, the problem lies with the earmold used in the hearing aid. The earbud may not fit well with the rest of the device, or simply be of poor quality. In this case, the insert needs to be replaced.

Also, squeaking is not ruled out if The device itself is of poor quality.. If you purchased a hearing aid at a low price, consider purchasing a higher quality model. Of course, the presence of marriage is not excluded in the hearing aid of any model, but the name of a well-known manufacturer is better insured against the presence of a malfunction. You can also consult with other people who wear hearing aids: they can often tell you where to buy a good device.

The problem may be in the setup of the device, if it goes astray or is simply poor quality.. To adjust the device, you should contact a specialist - an audiologist-adjuster. If your regular audiologist cites any other reason for the device's failure and refuses to reconfigure the device, we strongly recommend that you find another, more competent specialist. Typically, fitting a hearing aid is a complex and lengthy process; The audiologist should not refuse to help you under any circumstances if you claim that you need to readjust your hearing aid.

And the thing is that the distance between the receiver (speaker) and the microphone system is small. And because of the small distance, the high-frequency shortwave sound that is received by the microphone and amplified many, many times, sometimes gets back into the microphone. This circumstance causes its self-excitation. And the sound gets there due to the very small gaps between the earmold and the ear canal. Thus, the louder the hearing aid, the more whistling.
To avoid this problem, you need to make sure that the earmould fits snugly in your ear. This is what an individual insert is made for.
The problem of whistling is also solved by the program itself in setting up a digital device.

Among the analog programmable hearing aids there is the Swift Oticon model, it is not expensive for about 7000 rubles, and the sound gives like a top digital one. And all because the digital has not yet completely approached the analog sound. A digital hearing aid mainly provides noise reduction (a lot of technological gadgets), features (connection to a telephone, TV) and perhaps everything. Analog gives true pure sound. All from personal experience!

Best Hearing Aids. Premium class. http://www.dobsluh.ru/info/88-2012-04-17-17-26-23/

Why is it necessary to wear hearing aids in both ears?

The use of two hearing aids allows a person to restore the ability to determine the direction of sound in space, increases speech intelligibility. In addition, two hearing aids provide additional amplification, which is extremely important for severe hearing impairment, when one hearing aid does not provide the necessary amplification.

Over time, any mechanism, including the most modern electronic device, can fail. But far from always problems that have arisen require the participation of a master, sometimes restoring the device's performance is within its power and by itself.

This statement is also true in relation to hearing aids, since minor problems occur at any stage of operation. What faults can we fix ourselves?

1. The hearing aid does not turn on:
   • The most likely cause is insufficient battery power, so all that needs to be done is to install a new battery.
   • Sometimes when installing the battery, the polarity is not observed. In this case, it is enough to first remove and then insert the battery correctly.
2. The hearing aid is buzzing or buzzing:
   • The charge is running out. The battery needs to be replaced.
   • The reason may also be a loose fit of the lid of the box where the batteries are located. It is necessary to close the cover carefully, in order to avoid breakage of fasteners.
3. The hearing aid emits a weak signal, or is completely silent:
   • Check if the hearing aid is in working mode. If not, enable it.
   • There is a possibility that the volume level is at a minimum. Turn up the volume.
   • Another possible cause is a loose fit between the in-the-ear hearing aid or the BTE earmold and the ear canal. Remove and install the internal device again.
   • It happens that the hearing aid is clogged with earwax, so it will need to be cleaned and, possibly, a subsequent consultation and adjustment with an audiologist.
4. The hearing aid is whistling:
   • This effect often occurs at excessively high volume levels. Reduce the volume of the unit using the appropriate device.
   • The cause may also be the release of earwax that has accumulated in the ear canal or got into the hearing aid. All that needs to be done is to carry out hygiene procedures and clean the device itself. If necessary, you can seek the help of an audiologist.
5. The hearing aid transmits intermittent or distorted sounds:
   • Often the reason is the high volume level. Lower it.
   • It is possible that the battery life has exhausted itself. Use a new battery.

Another popular question is why does the hearing aid make noise?

It happens that noise occurs due to a failure of previously set parameters. The presence of noise in the device may also indicate the wrong selection of the device, its excessive power. There are several ways to solve this problem: set the minimum frequency level on the existing device or choose another less powerful hearing aid.