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Roadblock for noise



Noise music enemy number one, and to successfully deal with it, we must first understand its nature. The first cause of outsiders (and therefore undesirable) sounds obvious. This noise transmitted from outside the cabin. The second factor leading to vehicle noise, vibration occurring when the machine is moving: vibrations propagating through structural elements are emitted into the cabin noise and form.Vibration source can be the engine, transmission, suspension and trim body resonance of individual elements, mechanical shocks, etc. By the way, the speakers work often gives rise to interference resonances.

In turn, the materials that are to become an insurmountable obstacle to the noise, separated by counter methods (reflection, absorption, damping), typical application areas (doors, engine compartment, wheel arches, floor, ceiling), and its physical structure (liquid, foam, spray, solid). Therefore specialize in this area manufacturers approach the problem in a comprehensive and usually offer a list of materials, taking each his <defense sector>. Requirements for such products is very high. Besides the fact that silencers should be as effective in fulfilling its primary function is the sine qua non of their non-toxicity, resistance to high temperatures, moisture, as well as technology and ease of use.

Now on specific examples. As a practical sample products take American company Cascade Audio Engeneering (CAE), known under the brand name V-Blok. Interestingly, the products of the company in the U.S. is gaining markets in Europe. And one of the reasons for the popularity V-Blok is that all materials CAE absolutely harmless to human health, as in the Old World, as we know, environmental issues are taken very seriously. In the Russian market, the manufacturer is also not the first year and a well-deserved reputation as one of the most irreconcilable fighters for clarity. Number 1 at CAE listed noise-proof water-based paste VB-1. It is used to eliminate vibrations large area panels, curved and irregular surfaces and also for the treatment enclosure speakers. It is noteworthy that the VB-1 is versatile and extremely well to metal, plastic and wood, extinguishing the oscillations in a wide frequency range (10 Hz to 40 kHz). For maximum effect, apply two coats of a thickness not exceeding 3 mm, the treated surface does not let the noise of the entire life of the car.

In turn, VB-2 and VB-2HD (it is thicker) are polymeric adhesive materials designed for damping SAE (converting vibration energy into thermal energy) of oscillations of sheet metal and plastic. They produced pieces of different sizes and thanks to universal adhesive layer, which can withstand heat up to 200 degrees, seize virtually any surface. It should be noted that the VB-2 and VB-2HD absorb noise is twice as good mastic asphalt-based resins, while being 40% lighter and much more manufacturable.

For floor treatment from a range of car interior Cascade Audio Engeneering best club VB-3. As its structure, it consists of two layers reinforced neoprene foam, separated by a thin plate of lead. Accordingly, the bottom layer is a suspension for lead <filling> and the upper acts as insulation. As for the movable lead plate, it is an effective barrier for the noise arising from contact with the road during movement of the machine. At the same time, despite the presence of VB-3 lead layer, this material is easy to give the necessary form.

Composite material VB-4, in principle, the same as the VB-3 application areas (floor, walls salon, wheel arches), but differs from it in structure. The first line of defense heavy, soft and flexible vinyl weight. If coming from the pavement sound waves still seep through the vinyl, they are offset by a separating layer foam. At the same time prevents the penetration of the foam into the cabin heat and moisture. For processing engine compartments Cascade Audio Engeneering advises to use VB-TS. As well as the VB-3, this composite is struggling with the noise in two ways: absorption and reflection. It consists of a heat-cm layer of soundproofing foam retention noises midrange, and polyester film which is metallized chemically pure aluminum having a high reflectance. The reflective surface allows the use of VB-TS at ambient temperatures up to 205 degrees. Other advantages of this material are the presence of a filler, water repellent, and that VB-TS is stretched by 10% and provides a wide contact surface with any complicated.

Several stand out special pads Deflex Powerpads. These items are attached to the body of the car directly behind the speaker magnet head and prevent the occurrence of standing waves inside the installation volume that prevents the destruction of the diffuser and improves sound quality. Set Powerpads easy and have a lifetime warranty.
Original article source cxem.net

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