The active noise reduction of cars is favored by many of our car friends. The noise of cars is the last thing we want to encounter in our daily driving. How to use the active noise reduction of cars is what many of our car owners are more puzzled, especially thinking Owners who want to buy a car should have a better understanding of this configuration.
The principle of car active noise reduction
In a car, the noise emitted by the engine and the suppressive noise emitted by the audio system are superimposed and then cancel each other out to achieve a noise reduction effect. However, in some places, car noise reduction and earphone noise reduction are still handled differently. Because the noise emitted by the car engine at different speeds is basically in a fixed state, before the production of the vehicle, the manufacturer generally collects the noise data of the engine in advance, and calculates the wave that is opposite to the noise at different speeds through the system. So as to cancel the noise.
It uses the engine speed as a reference signal, and then generates corresponding noise suppression audio signals through several muffler speakers in the car to eliminate noise. The microphone installed on the roof has an error correction function, which can correct the noise suppression audio signal. With this complete system, it does not require too many cabin noise reduction materials to obtain excellent noise reduction effects, and this system has also begun to be popularized in some mid-priced models, I believe ordinary consumers Soon I can feel the quiet effect it brings.
Application of Active Noise Reduction in Cars
1. Generally, the noise signal and engine revolution information received by the microphone installed in the specific area of ​​the car cabin will be input to the car amplifier, and the amplifier will use the internal unique algorithm to make the car speaker emit a second harmonic with the engine Noise inverted waveform. Due to the interference effect of the waves, the sound waves of two inverted waveforms will cancel each other when they meet in the air, so that the second harmonic noise level in the cabin is greatly reduced. The microphone installed in the car can continuously monitor and measure the noise conducted by the power system into the cabin, and adjust the waveform and amplitude of the inverted wave emitted by the speaker in real time, so that the passengers in the car can get rid of the noise of the vehicle during operation.
2. Active noise reduction is not about isolating the noise of the engine, but selectively dealing with various inappropriate and unpleasant noises. The ideal engine sound will increase linearly with the increase of engine speed. This is exactly the car Manufacturers continue to adjust the engine sound characteristics goals they pursue. Therefore, vehicle owners (especially experienced drivers) do not need to worry about not being able to judge the working status of the vehicle because they cannot hear the sound of the engine.