what are the types of hearing aids?

Traditional hearing aid components include: microphone, amplifier, receiver, volume control, audio control, inductor tor, battery.

Hearing aid are used to convert sound signals into electrical signals, amplify them and then convert them into acoustic signals. In the energy conversion process, the transducer function is realized by microphone and receiver.

The receiver is another transducer, just the opposite of a microphone, that converts amplified electrical signals into acoustic signals or mechanical vibrations that are transmitted to the ear canal. The receiver converted to sound signal is an air conduction receiver, the receiver transformed to mechanical vibration is a bone conduction receiver.

Volume control volume control is a variable resistor or potentiometer, used to adjust the current through the amplifier, the volume changes with the electrical signal resistance change. Turn up the volume, and you’ll need more current. When the volume is turned down. The current flowing through the amplifier decreases making the sound lighter.

In the programmable hearing aid, through the computer programming to carry out all kinds of fine-tuning adjustment, so that the adjustment is more accurate, can be more fine compensation for hearing loss, including.

 1. the hearing aid is a hearing aid

2. The maximum output of the hearing aid can be controlled.

3. Automatic gain tightening control, control the sound within the comfortable loudness range.

4. Gain control (GC) modulates the gain of a hearing aid

The greater the power of the hearing aid, the larger the battery power, the greate its volume. If the battery is not enough, it will limit the output pressure of the hearing aid.

Hearing  aids require small size, constant voltage, reliable quality, long life, environmentally friendly batteries. The batteries in hearing aid are zinc air batteries ( on batteries)

Hearing aid accessories can include an audio input and an inductance coil.

Most hearing aids have a connector or jack for audio input, which is important for listening to the radio or watching TV. Because the audio signal comes directly from the sound source and is not converted from sound to electricity, the quality of the input signal is better than that of the microphones.

An inductance coil is a magnetic induction coil that can respond to the electromagnetic field leaked from the receiver on the aircraft, convert it into n electrical signal and amplify it so that the hearing aid can be used to listen. Its advantage is that it can not produce a roar, no interference, high signal to noise ratio in a noisy environment. Signal to noise ratio （ ANR）is the difference between the speech signal and the ambient noise.