Explanation of the principle of hearing aids

Over-the-counter hearing aids have three important components, namely microphones, amplifiers and speakers.
The working principle of TWS hearing aids is that the microphone picks up the sound, the amplifier amplifies the sound, and then outputs the sound through the receiver (speaker).

A Bluetooth hearing aid is a small loudspeaker that amplifies the sound that was originally inaudible, and then uses the residual hearing of the hearing-impaired to send the sound to the auditory center of the brain, and feel the sound.

Channel explanation of self-fitting hearing aids

It refers to the DSP (digital signal processor/Digital Signal Processing) of the fully digital hearing aid, which is divided into multiple independent circuits to calculate and process the sound of different frequency bands. Since each unit processes the signal independently and does not affect each other, it is called a channel.

①The more channels there are, the wider the range of adjustment of the hearing aid can be, and the higher the price. ②The greater the current of the hearing aid, the shorter the battery life will be. ③The channels generally have 4/8/16/32/64 or even higher channels.

Howling principle:

Acoustic feedback is commonly known as howling. The brief principle of howling is that when the receiver (speaker) outputs the sound amplified by the amplifier, part of the sound energy is collected by the microphone of the hearing aid and then amplified.

The main reasons for howling: (1) The sealing problem between the hearing aid earplug and the ear canal; (2) The volume of the hearing aid is too high; (3) The hearing aid itself does not have the function of suppressing acoustic feedback.

How to improve howling: (1) Choose a suitable earplug; fit the earplug tightly to the ear canal or replace it with a larger earplug to ensure that the sound does not leak; (2) Wear it well before turning it on.