Sound absorbing material
Sound absorption is simply the ability of some material to absorb sound vibrations by turning them into heat, which changes the wave form into an energy suitable for human hearing. Sound absorption comes in many different forms, with differing levels of absorption ability depending upon the nature of the material and its application. Sound absorption also varies between material types, with some materials having better sound absorption properties than others. For example, polyethylene (also known as PET, or polypropylene) has excellent sound absorption and sound deflection properties. However, it is difficult to find furniture made entirely of PET because it tends to be a very soft and malleable material.
The advantages of using sound-absorbing materials include a reduction in outside noise, reduction in ambient temperature, reduction in energy use and ventilation. A material with superior sound absorption and sound deflection properties is perfect for passive solar insulation, as well as many other applications where sound diffraction is important. Foam and fiberglass are two materials frequently used to create sound-absorbing materials in modern housing. Fiberglass generally works best in smaller rooms while foam works well in larger rooms. Foam may even absorb all outside noise if a sufficient amount of cushion is installed between the foam panels and the wall(s).
When considering sound absorption, there are three main categories: damping, diffusers, and dampers. Dampening refers to any material that decreases the sound waves that reach a room by diminishing the kinetic energy that passes through the material. Diffusers disperse sound energy in the room by modifying the frequency and wavelength of the sound waves. These two types of damping are typically combined in one material, such as a piece of furniture. Furniture often contains dampening materials that can be individually adjusted according to a person's needs.
The diy acoustic panels I constructed recently are a perfect example of damping material that can be adjusted individually. The frame is made from a thick nylon fabric that has been dyed black. The fabric acts as a dense barrier to sound waves, preventing them from entering the space between the frame and the walls. Each wall is installed with four evenly spaced fabric slits, giving me a total of twelve spaces.
The slits allow sound to be absorbed through a tight layer of material, without the material being visible to anyone inside the room. To make this material more effective, each slit is connected to an aluminum or copper wire. The connection between each wire is completely hidden by the fabric, so anyone standing far away cannot hear the wire connections. This makes the diy acoustic panels system extremely effective at sound absorption.
The diy acoustic panels I have constructed are an example of high quality sound absorbing material. To make sure they are highly effective, all of the slits are perfectly spaced. My design team built each section of the panel to be perfectly centered. Because of their precision construction, the slits are connected tightly and permanently in place. The material also weighs nothing, so they are light enough to be carried anywhere.
When selecting the appropriate sound-absorbing materials, you need to be especially careful of the spacing between the slits. If the spacing is too close, sound waves will travel through the entire material without being absorbed. However, if the spacing is too far apart, sound waves will be reflected instead of traveling through it. The ideal solution would be to make sure that each slit is exactly one half inch to one and a half inches away from each other.
Another way to achieve the right spacing for your material is to use green glue. Green glue comes in very concentrated form; however, you can make small amounts with a syringe. You simply dampen the green glue with water, squeeze some of it into the area that needs soundproofing, then spread it around in the same fashion as you did with the material slabs. Green glue is a strong barrier to sound waves, which means that it is a perfect choice for insulating walls, doors, ceiling, and flooring.