Three basic principles are used to reduce noise. They include space, mass and dampening. Noise waves cannot extend beyond a certain range; where there is more space, there is more noise reduction. Noise absorption techniques work well with soundproofing principles, which include dampening and space. This process involves changing the characteristics of a noise by preventing it from echoing, reverberating and reflecting, all of which are involved with noise absorption. Restricting the noise-making device to an isolated area is another way to keep noise under control. Carpets, upholstered furniture, acoustical ceiling tile and soundboards are different methods used for noise absorption.
Sound waves cannot effectively penetrate heavier objects with more mass. When it comes to noise reduction, erecting heavy objects can reduce or eliminate sound. Noise reduction doesn't allow sound to escape from a particular area. Objects such as thick heavy walls could reduce noise levels significantly. Barriers such as soundproofing board can be placed over walls and soundproofing doors can replace standard doors to eliminate or reduce noise levels from entering or leaving a particular area.
Source modification involves changing the characteristics of a particular sound or using dampening techniques to keep it at a tolerable level. Techniques such as diverting, or changing the direction of noise, are a method of noise control. Managing how the noise is transmitted by changing, adding or taking away parts is another. Source reduction and dampening techniques vary; they both work to eliminate sound at the source or by altering its characteristics.
Noise reduction materials such as vinyl and cotton are some of the items that are used as noise insulation materials. Bonded cotton batt insulation or mass loaded vinyl are two types of materials used for noise reduction processes. Rubber mats and insulation, and polymers and wax are two other items that are used for this purpose. Items such as acoustic wall panels, soundproof doors and fabric panels are used to degrade or to stop noise. Isolation tape, soundproof glass and sound isolation tape are materials that disrupt sound waves and lower noise within an environment.