Noise pollution has become a major issue in today’s world, and people living in noisy and crowded cities have no respite from the sound inside their homes. Developments in technology have led to the creation of new products to the homeowner from noisy neighbors and road noise through soundproofing of walls, ceilings and floors. Soundproofing is a method of reducing the sound pressure thereby blocking most of the noise from entering the interiors of your home. Soundproofing technology uses two different ways to affect sound energy; one is noise absorption and the other is noise reduction.
Noise reduction technique simply blocks the passage of sound waves while noise absorption technique functions by transforming the sound waves and involves echoes, reverberation, resonance and reflection. There are many sound proofing methods that are followed; they include increasing the distance between the source and the receiver by using noise barriers, sound baffles and active anti-noise sound generators to block the sound energy from penetrating the room. Let’s take a look at techniques employed in soundproofing walls.
Sound energy travels through substances in longitudinal waves and the energy produced in one place will have greater effect in another. Sound waves are produced when an object vibrates due to force applied on it. Different frequencies of sound produce different energy levels and the sound can be controlled in three ways:
• Elimination
• Passive Absorption
• Noise Barriers
Though elimination is the best method, it is not a practical solution in most cases. In passive absorption, when sound waves are passed through absorptive material such as mineral wool or acoustic foam, they are forced to change the direction so many times before they are fully allowed to pass through the absorptive material, thereby reducing their impact drastically.
Talking about barriers, these are generally constructed using non-porous materials. This is because a barrier must have weight, density and low resonant frequency to stop sound energy. When sound pressures increase, it will increase the sound power. Higher power levels of the sound will cause the encountering surface to vibrate at the resonant frequency which eventually makes the barriers vibrate.
