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Specialist in Acoustic Components  

 

 

 

Introduction of Electret Condenser Microphone 

 

 

structure of microphone

working theory

microphone testing

microphone circuits

Directivity

How to choose:

Electret type: Back electret type provides better low frequency response, but it costs higher.
Dimension: It is difficult to make high sensitivity with the small size. The thinner of the dimension is the higher it costs.
Directivity: Omni-directional type microphone meets most kinds of consuming products, our R&D team will support your special requirement.
Connection: Soldering type, DIP type, and Spring contact type.
Rubber holder: Rubber holder can reduce the interference from the inner machine or from hands touch.

FAQ:

Echo/ howling: This situation usually happens when a microphone is too close to the speaker or face to the speaker in wrong angle.

Noise signal: The microphone should stay away from any components which might send signal such as antenna and speaker. The cleaner the power source is, the fewer the noise signal is.

Pipe vs. resonance chamber: Limited by the industrial design, it is hard to set microphone near the surface of the case. Therefore we use a pipe to lead the sound, but the frequency response might loss if the length of pipe is too long or the volume is too big.

The directivity: Considering the ventilation of air holes in the back, the closer of the distance between the air holes and the sound hole is, and the straighter the angle is, the better result of directivity is.

Static electricity: FET is very easy to be punctured by static electricity; therefore we need to take measure to prevent it in processing or in transit.

The temp. of ferrochrome: The too high temp. or the too long welding might do damage to the microphone.