Acoustic foam

Acoustic foam is an open celled foam used for acoustic treatment. It attenuates airborne sound waves by increasing air resistance, thus reducing the amplitude of the waves. The energy is dissipated as heat. Acoustic Foam can be made in several different colors, sizes and thickness.

Acoustic foam comes in a variety of sizes and can be attached to walls, ceilings, doors, and other features of a room to control noise levels, vibration, and echoes.

Many acoustic foam products are treated with dyes and/or fire retardants.

Uses

The objective of acoustic foam is to improve the sound quality by removing residual sound in any space. Not only does the resonance and echo effects are kept in check, but the ambience of the room is contained within thus making it better soundproof for the outside.^[1] This purpose requires strategic placement of acoustic foam panels on walls, ceiling and floors, effectively eliminating resonance within the room.

Acoustic enhancement

The objective is to enhance the properties of sound by improving speech clarity and sound quality.

For this reason, acoustic foam is often used in recording studios. The purpose is to reduce, but not entirely eliminate resonance within the room. This is achieved by placing similar sized pieces of foam, often in the shape of cones or triangles, on opposite walls.

How Acoustic Foam Works

Acoustic foam is a lightweight material made from polyurethane foam either polyether or polyester, and also extruded melamine foam. It is usually cut into tiles - often with pyramid or wedge shapes - which are suited to placing on the walls of a recording studio or a similar type of environment to act as a sound absorber, thus enhancing the sound quality within a room.

Acoustic foam reduces or eliminates echoes and background noises by controlling the reverberation that sound can make by bouncing off walls. This type of sound absorption is different from soundproofing, which is typically used to keep sound from escaping or entering a room.

Acoustic foam typically deals more with the mid and high frequencies. To deal with lower frequencies, much thicker pieces of acoustic foam are needed; large pieces of acoustic foam are often placed in the corners of a room and are called acoustic foam corner bass traps.

Usage

Acoustic foam is primarily used in recording studios to minimize sound echoes. However, it can perform the same function in home theaters, manufacturing facilities, equipment warehouses, home offices, gymnasiums and auditoriums. It can be placed in any room where an optimal sound mix is desired.

Acoustic foam is often used to reduce echos by attaching it to the walls of large rooms, like churches, synagogues and temples. Using jagged acoustic foam to baffle the sound can help, as does hanging sound baffles that break up the empty space in high ceilings and large rooms.

The effectiveness of acoustic foam panels can be increased by ensuring there is an air gap between the foam panels and the walls. Doing this exposes a great surface area of the foam panels to incident waves increasing the amount of absorption. Spacing the foam from the wall also has the advantage of reducing any damage spray adhesive would have on a wall or painted surface.

In some restaurants the pictures on the walls can be acoustical panels, obviously with an image over it.

References