Auto noise reduction: what is it?

In the next article, we will definitely tell you how car noise isolation is carried out. But let's first try to figure out where the unnecessary rumble comes from in the car interior and with what materials it is customary to deal with it.

The nature of vibrations and overtones in a car can be very different - different sources of noise, differing in intensity and frequency spectrum. But still, the main source of extraneous sounds and their excellent conductor is the metal of the body. After all, for sure everyone is familiar with this special rumble, heard from a knock on any metal object. Of course, the knock of the rocker on the valves, the beating of the suspension and shock absorbers, the vibration of the muffler, the rotation of the bearings - all this transmits a lot of extraneous sounds to the car body and, accordingly, to the interior. And if we add to this the noise of a running fan and the rattling of the plastic panels of the passenger compartment, then the sound background of a different frequency range created inside the car will get on anyone's nerves.

Multilayer car soundproofing

We think that everyone understands that there are no universal materials for noise isolation that would be able to cope with sounds of all frequency ranges. Therefore, the best option is the so-called "sandwich" - a coating consisting of several layers, each of which has a specific role.

So what is in the sandwich?

1. Bottom layer:

• vibroplastShumoFF M2, M3 and M4 - materials with high damping properties (glued to plastic or metal). They increase the weight of the base and, accordingly, reduce its resonant frequency, convert the energy of sound vibrations into thermal energy. That is, by gluing this layer, instead of "ringing" you will hear only its deaf echo, which, like an echo, will gradually subside.
• vizomat Shumoff Mix , Mix F - usually is a combined multilayer material designed to remove powerful vibrations on the bottom of the car. It consists of several layers, which include - rigid aluminum foil, various mastic and bituminous layers.

2. Top layer:

• splenitis NoiseFF P4 , P8 - highly elastic materials that remove airborne noise, i.e. voices, signals and other higher noise levels. Mounted on top of vibration damping materials. In addition, it is installed as thermal insulation. Sometimes special noise-absorbing materials with a lead or aluminum layer are placed in the middle, which create a kind of acoustic screen (this type of insulation is called a "sound barrier"). Mounted on doors, roof, trunk.

In addition, it is also desirable to make a sound-absorbing layer (bitoplast or hermeton 7, 15, 30) - a very soft material that resembles foam in structure. Used to dampen internal squeaks. Installed at the joints of plastic and metal

You can read about the advantages of materials of the ShumoFF trademark in our previous article: Car noise isolation: why is it needed and what to choose?