For the pursuit of perfect people, car noise is often unbearable, in the ordinary life, because of noise, noise, noise and other voices together, making the car in the driving, the car is not quiet, there is irritable noise. Generally speaking, there are four sources of automobile noise: engine noise, tire noise, air noise and body structure noise. 1. noise. In addition to the mechanical sound emitted by the body, it also includes the noise of the intake system, that is, the high speed gas enters the cylinder through the air filter, the intake pipe and the valve. In the flow process, a very strong aerodynamic noise will be produced. The engine noise is mainly transmitted to the cockpit by the retaining wall and the front chassis of the cab. 2. tire noise. The general tire noise consists of three parts: one is the air flow of the tread clearance and the air noise around the tire; the two is the vibration noise caused by the vibration of the matrix and the pattern part, and the three is the pavement noise caused by the uneven pavement. 3. air noise. One is the noise of the air, which is caused by the pressure change around the body around the body; two is the wind leakage, or the sound of suction, the noise produced by the interaction between the cab and the body crevice and the air flow around the body; the three is the other noise, including the cavity resonating, etc. 4. noise of body structure. It is mainly influenced by two factors, one is the vibration transfer mode of the body structure, and the two is the noise caused by the vibration of the metal components in the body. We can take two ways to deal with the noise: the first is to fundamentally let the noise disappear or reduce, and we should fundamentally eliminate the first to know where the noise of the car comes from. We should find out different sources of noise on the vehicle so as to cure the noise and get rid of it. For example, tire noise can choose a tire with low tire noise to reduce noise. This is the fundamental solution to the problem. And the second is to do the whole car sound insulation project, which is the way most people use so we focus on it, although the noise outside is still not changed, but the seat in the cab is still a lot of quiet. Sound insulation is generally suitable for cars equipped with lower, more comfortable or lower end cars. If the high-end car, the original sound insulation has been quite good, and then spend money to do soundproof instead of superfluous. Also, a car friend raises questions about the effect of the automobile upgrading after sound insulation, and thinks that the effect of the noise after the car's upgrading is very little or even no effect. It also increases the weight loss and fuel consumption of the vehicle, which is mainly due to the improper brand and quality of the sound insulation products chosen by the car friends. How should car sound insulation be chosen and how to do it? The first step is to remove the door inner lining. The second step: the mute material installation. Remove the visceral pollution, oil pollution and residual glue. If it is not clean, the damping material is not easy to paste, and it is easy to fall off. The preconditioning agent is applied to the surface before vibration reduction. The third step: absorbing damping and sound absorbing materials. The appropriate size of the damping material is cut into the door, and the material surface is scraped evenly with the rubber scraper, so that it is fully attached to the car door, and the sound absorbing material of the suitable size is attached to the vibration damping material merchant and the back of the loudspeaker should be the center when sticking. The fourth step: the proper application of the hose. If the impact on the handle of the switch is affected in the paste, install the wiring hose on the handle of the door switch. Fifth step: paste the sound material. The appropriate size of the counter sound material is pasted on the lining board, and it is pressed evenly with the rubber scraper, so that it is fully attached to the inner lining board, and the small holes used in the inner lining board plug are not attached. Sixth step: sealing material. Sealing material around the speaker and fixing plate will enhance fuel consumption.