When sound travels in a given medium, it strikes the surface of another medium and bounces back in some other direction, this phenomenon is called the reflection of sound. The waves are called the incident and reflected sound waves.

As sound travels through a medium such as water, it gets absorbed – caught by the molecules within the medium. They do this by stealing some of the energy from the sound wave. The absorption in sea water is much greater than would be expected due to the viscosity of pure water.

Walls of aroom are good reflectors of sound. Wood, carpets, curtains, clothes and even our bodies absorb sound better and reflect less. In fact, soft surfaces are better absorbers of sound whereas hard surfaces are better reflectors of sound.

When the wall of a building reflects sound, even though that wall may appear rough to the naked eye (concrete or brick or whatever), from the perspective of sound, that building is a specular surface which reflects sound in a mirror-like fashion.

As a sound wave hits the meta-mirror, it reflects off of its curved surfaces and interferes with itself. Such a device would not only be able to reflect light in different directions, however, it could also split a single wave into two arbitrary directions.

In addition, aluminum foil reflects and isolates heat as well as the competition yet it offers superior acoustical and vibration shielding. Therefore, heat transfer by radiation is minimized. It is the first of these benefits that helps explain why aluminum foil protects so well against sound.

sibeliustalo23auerniitty_web. jpg. Wood is a light material, so as such its sound insulation performance is not particularly good. Neither does a thick, dense-surfaced and smooth wooden structure dampen sound particularly well, so wood alone is not a good absorption material.

Types of Soundproofing Materials

• Acoustic Foam – This material, commonly called Studio Foam, has a distinctive wedge or pyramid shape that is highly effective at absorbing sound.
• Sound Insulation – Sound insulation are batts made of mineral wool, rock wool, and fiberglass, designed to fit in between the studs of walls.

While MDF is the go-to choice for many indoor soundproofing applications, there are situations where it is not optimal because of its water-absorbent properties. Plywood would be the choice for sheathing your floor since non-sanded sheathing plywood is so much cheaper than MDF and is more resistant to moisture.

Recently, though, a variety of sound-dampening drywall products have become popular as a means of reducing sound transmission. They can be very effective at adding soundproofing to walls where it is not practical to reframe or use other structural methods.

Drywall offers superior fire resistance compared to plywood, making it the safer wall finish in most applications. This makes it a useful insulating material for flooring, ceilings, roofing, and wall cladding. Insulation offered by plywood can greatly reduce heating and cooling costs.

Aside from being less fire resistant, more expensive and harder to work with, plywood is the more durable of the two materials. Unfortunately, when plywood is damaged it is harder to fix than drywall. Drywall is more universally used, and it is much easier to find someone to handle your drywall needs.

Drywall