The use and correct selection of soundproofing materials is determined by the noise level we are dealing with and where that noise level comes from. If the unwanted noise originates from outside the room or the structure we are looking for soundproofing, we need to use barrier soundproofing technology. We must put a barrier between us and the noise we are trying to get away from. If our noise levels originate from inside the room, we will have to use absorption technology, trying to be soundproof. In some cases, we may have to use both barrier and sound absorption technology together to absorb excess energy from our room and prevent this energy from leaking into adjacent structures.
Building a Soundproofing Barrier
Barrier technology is exactly what its name implies. We build a barrier between our room and the noise source. If we live on a busy street and traffic interferes with our recording studio, we need to set up a barrier between us and the traffic between us. If we live in an apartment and have a noisy neighbor, we need to set up a barrier between our neighbor and our apartment. Barrier technology is not cheap to make and requires special construction techniques. One has to choose which materials to use and how much. It should also be decided which construction method we will use in the installation of our barriers. After building the barrier, we must place it in an existing structure. Care should be taken to mechanically separate our new barrier wall or structure from the existing room. We must use vibratory control assembly and assembly techniques.
Sound Absorption Technology
Sound absorption technology is a different kind. Sound absorption technology has nothing to do with mass, except for low-frequency absorption issues. Absorption technologies are generally lightweight and can be easily positioned. Absorption is a physical process in which sound energy is converted into heat. When this conversion process takes place, the sound energy is lost forever. Once changed to heat, it cannot be changed back to sound.
Sound Barrier Materials
Barrier technologies are produced with standard construction materials. Some materials used in barrier technologies include plywood, multi-density fiberboard, drywall, and even concrete and lead. Barrier technology materials are heavy and have high densities to minimize vibration. Vibration control becomes the design intent of an obstacle. Airborne sound energy hits the barrier and is then converted into mechanical energy. This mechanical energy passes through the barrier we have just built, and these vibrations must be systematically attenuated to ensure that they are attenuated when they enter our room. All noise problems are difficult and expensive to stop. The best we can try and achieve is to reduce the noise levels produced from outside to below an acceptable level.
Soundproofing Should Reduce Vibrations
To minimize vibration levels, we must build our barrier in a vibration-reducing fashion. The correct term for this construction methodology is constrained layer mass damping. We use different layers of material combined to create a mass that acts as a vibratory damping unit. Each layer of our several material barriers must be installed to dampen vibrations. For example, if we are using plywood and drywall as two of our barrier materials, we must combine these two materials together with another layer of material. The more materials used in building the barrier technology, the better generally. We can join plywood and drywall together using an acoustic adhesive that will provide the bonding advantages necessary to hold the two materials together. However, the assembled unit does not act as a single piece of material. Remember, our goal is to dampen vibrations and force them to pass through different materials with different densities. Done correctly, this can significantly reduce vibrations.
Sound Absorption and Soundproofing Materials
Sound Absorption technologies can be common acoustic foams, curtains, multiple fabrics and even furniture. Our acoustic goal with Sound Absorption technology is to provide enough of the selected material. Thus, we can cover all the necessary surfaces of our room that we want to soundproof. A combination of soundproofing materials usually works best. In most rooms where soundproofing our room is the goal, we must cover all wall surfaces with sound absorption technologies and even add additional materials throughout the room to absorb lower frequencies than standard acoustic wall treatments can handle. A large stuffed chair can be used to absorb lower frequencies that our acoustic foam panels cannot. If we want to scientifically solve and deal with our sound absorption problems, we can use low-frequency absorbers that are specifically designed to address low-frequency energy issues specific to our individual room. Soundproofing materials are problem specific. If we need to stop an unwanted noise from outside our rooms, we need to create a barrier between ourselves and the noise source. We need to use materials with high weight and density. Barrier materials include plywood, drywall, concrete and even lead. Barrier materials have mass and density. If we need to absorb unwanted energy from our room, we use absorption technologies.
