icrophones generally refer to microphones. Microphone, the scientific name is microphone, which is translated from English microphone (transmitter), also known as microphone, microphone. A microphone is an energy conversion device that converts sound signals into electrical signals. There are moving coil type, condenser type, electret and recently emerging silicon micro microphones, in addition to liquid microphones and laser microphones

The most direct and intuitive method is to visually inspect the two tin points on the microphone product board. If the tin point is independent, it is the positive electrode, and if the tin point copper is connected to the microphone shell, it is the negative electrode. Another method is to use a multimeter to measure the continuity test. One of the tin points and the shell is connected together is the negative electrode of the microphone product

Omnidirectional electret microphones Magnetic, ceramic and electret microphones are all omnidirectional microphone microphones, which accept sounds from all directions equally. At present, electret microphones are widely used in the field of acoustics. It is made of an insulating, highly polarized material. When the sound enters the microphone, the density change of the sound wave causes the negatively charged thin

ccording to the J.D. Power 2016 American New Car Quality Survey, among the problems reported by car owners, the entertainment system and voice recognition system-related failures accounted for as high as 23%. Renee Stephens, vice president of J.D. Power's automotive quality department, said that although speech recognition has made a little progress this year, speech recognition failures are still the most common problem

At present, the industry's best in-car active noise reduction system, its maximum operating frequency can only reach about 200 to 240 Hz (the active noise reduction frequency of some systems can reach 700 or even 1000 Hz), the environmental noise mentioned above Almost not in this range. Generally speaking, the frequency of sound waves is above 200 Hz, and police cars and horns are even higher. This starts with the principle of active