Absorption of airborne sound
Airborne sound, from engines etc., can be reduced by covering the surface by an absorbent made of porous foam, textile fiber or metal. The absorbed sound is converted to a very small amount of heat inside the absorption material. The absorption factor, between 0 and 1, tells you how effective the absorption is.
MicroPerforated panel absorbers (MPP)
If you have problems with cabin acoustics Micro Perforated Panels (MPP) are the solution for you. These panels are specially designed to have high absorption although they are only between 0.3 to 2mm thick. They can be made of metal, plastic or glass depending on your needs. They need to be mounted with an air-space distance from the wall and their additional advantages are higher fire resistance, longer life lower weight. Sontech is a Pioneer in MPP production and application, read more about our fire retardant sound absorber Acustimet, 100% metal 100% recyclable.
Structure borne sound is unwanted vibrations in solid structures. These vibrations can be dampened by using a dampening pad or by constrained layer dampening. In both cases the vibration energy is dissipated to heat inside in the damping material. The damping efficiency is measured in the unit “loss factor”.
One way to prevent unwanted sound is to Insulate. This could be done by isolating the source by a barrier or a hood. The isolation capacity is increased by the weight of the barrier and the insulation capacity can be further increased by using multiple barriers. The efficiency is measured in Transmission loss I.E how many dB are lost during the transmission.
Very often machine sound problems is spread through holes, cracks and other leaks. Sealing of these are an effective way to diminish the transmission of sound. Sealing is a high focus area for Sontech.
Nature puts different requirements on isolation materials. It could be to protect a pipe or a structure from coldness or heat. Or wise versa, protecting the outside environment from the pipe, sometimes to prevent condensation of water. These are thermal problems that could be solved by proper insulation.