Soundproofing

About Soundproofing and Soundproofing Manufacturers Including: Acoustical Ceilings, Acoustical Panels, Noise Pollution, Sound Barriers & Sound Proofing.

Soundproof materials are used create a variety of products, from earplugs to wall panels meeting regulatory standards for reducing noise and creating a safer, quieter environment. Two types of noise are airborne and structure borne noise. The former refers to noise radiating directly from engines, transmissions and other rotating equipment. Structure borne noise refers to vibrational energy imparted to the walls or other enclosure devices. One approach to eliminating or controlling noise is containing noise at its source by using mufflers, engineering controls, etc. Another is identifying, isolating and treating with sound barriers, absorbers and dampers the many paths along which noise travels. A third approach is reducing noise at the listener with headphones, earplugs and so forth. Soundproofing solutions typically require a combination of these approaches.
 
Soundproof materials can function as sound absorption, vibration damping and sound barriers. Sound absorption is achieved with the use of soft, porous, open-celled materials, such as flexible polyurethane foam and other acoustical foams, which provide non-reflective surfaces in order to reduce noise levels in applications, including machine enclosures and housings and medical and industrial equipment. Sound absorption is directly related to the amount of treated surface area (i.e. the more reflective surfaces treated, the greater the sound absorption). Vibration damping materials reduce the amount of vibration energy transmitted between surfaces constructed of rigid materials, which are typically sympathetic to vibrations at one or more frequencies. Sound barrier materials, such as flexible mass loaded vinyl, combine mass, flexibility and limpness to form a barrier between the noise source and the controlled area. Sound barriers are often combined with sound absorption materials to create truly effective noise control composites.
 
Soundproof environments or noise control efforts are necessary for the health and safety of employees, employers, customers and bystanders in the work place. It is important to be aware of government regulations for noise control when building a structure or manufacturing a product. Government regulations require noise to be controlled or hindered above 70 dB in a work environment. Schools, airports, offices and other buildings require a certain amount of sound reduction to be functional and safe. Work environments are a major concern when load machinery is involved. In each circumstance, airborne noise and structure borne noise need to be monitored.
 
Soundproof materials are necessary in nearly every industry. Aerospace applications include engine exhausts, cooling systems and diffusers. Industrial applications include fans, ducts, air compressors, mufflers, moving machinery, exhaust vents and inlet silencers. In the transportation industry, soundproofing applications include locomotive, trucking, automobile, construction and mining equipment. Soundproof services offer measurement, analysis, isolation and identification of noise sources. Treatments are recommended based on noise spectra, operating environment, weight and material cost requirements. Finally, the new installations are tested to see if noise is sufficiently reduced.

Soundproofing and Soundproofing Manufacturers Images Provided by Eckel Noise Control Technologies

Types of Soundproofing

• Acoustical baffles are constructed of one or two cores of dimensionally stable medium density glass fiber and suspended vertically from a ceiling structure. Acoustical baffles are designed for areas where standard acoustical ceilings are not feasible or as an additional acoustical treatment in existing spaces.
  
• Acoustical blankets consist of polyvinylchloride outer shells and acoustical batting. Acoustical blankets can be hung from vertical uprights or attached to a frame, enclosing a piece of equipment to absorb and stop noise.
  
• Acoustical ceilings consist of a suspended ceiling grid and high sound absorption lay-in acoustical panels or tiles and provide a lightweight and attractive ceiling system. Acoustical ceilings, which are quickly installed, can be used to control the quality of sound effectively in a specific space.
  
• Acoustical enclosures are used when sound must be prevented from spreading from one area to another. Acoustical enclosures include recording booths, industrial enclosures of all kinds, highway walls and noise barrier walls.
  
• Acoustical foams are used to line sound-reflective surfaces. They reduce noise by allowing the sound energy to penetrate into the material and be dissipated by its cellular or fibrous nature prior to reaching the reflective surface.
  
• Acoustical panels absorb unwanted noise.
  
• Barriers provide a high density layer used to separate or prevent noise from entering a certain area or leaving a contained area. Common uses for barriers are bulkheads, firewall treatments, cab floors and pipe wraps.
  
• Clouds are panels similar to acoustical baffles but are hung in a horizontal position from the ceiling or roof structure.
  
• Damping materials aid in the control of vibration and structure borne noise often through friction or time. This method is common with sheet metal panels, cab enclosure panels, boat hulls and deck plates and HVAC ductwork.
  
• Diffusers scatter a sound wave from a surface. Sound direction is changed so listeners may experience sound coming from different directions at equal levels.
  
• Intake silencers decrease the noise and destructive low frequency pulsations at blower inlets.
  
• Isolators can reduce vibration by having greater attenuation in one direction than the other and are often found installed under some defined load factor between two surfaces, such as generator pads.
  
• Modular acoustical panels are easy-to-use portable panel products, such as partitions, wall-mounted panels, baffles and privacy screens.
  
• Noise pollution refers to any unwanted and unpleasant sound.
  
• Reflectors are used to regulate the amount of sound that is reflected off a surface. Reflectors are often used in acoustically sensitive settings.
  
• Silencers reduce the level of sound through either absorptive, reactive or a combination of mechanisms.
  
• Sound absorbers are noise control materials and are directly related to the amount of surface area available to be treated. Sound absorbers are frequently found in machine enclosures, housings, industrial environments and medical, marine and transportation applications.
  
• Sound barriers use a walls of high density material to reduce roadway noise.
  
• Sound proofing refers to the methods used to reduce the intensity of sound.

Soundproofing Terms

A-Weighting – The filtering system in a sound meter that allows the meter to disregard lower frequency.

Absorption Coefficient – The ratio of the sound absorbed to the sound incident on the material or device.

Acoustical Analysis – A determination of the level of reverberation or reflected sound in the space for which the building materials are a factor. Acoustical analyses also determine how much acoustical absorption is needed to reduce reverberation and unwanted noise.

Acoustical Material – The material used to change a sound field by absorbing, damping or blocking acoustical energy.

Acoustics – The science of sound, which includes its creation, transmission and effects.
 
Airborne Noise – The uninterrupted transmission of noise into the atmosphere. Airborne noise can be controlled by absorption or by being blocked.

Ambient Noise – The sounds within a given environment from many different sources.

Anechoic Room – A test chamber lined with absorbent acoustical material used to eliminate sound reflections and to determine the sound radiation characteristics of equipment.
 
Bel – A unit of measurement referring to sound intensity. One bel equals 10 decibels.

Damping – The process of dissipating mechanical vibratory energy into heat. Damping materials are used to apply to vibrating surfaces in order to reduce the noise radiating from that surface.
 
Decay Rate – The rate at which sound will fade when the noise source is removed, expressed in dB/sec.
 
Decibel (dB) – A unit of measurement referring to sound intensity that is equal to one tenth of a Bel.

Dissipative Silencer – A device inserted into air ducts or openings that reduces the noise transmitted through the ducts or openings. Noise reduction is accomplished by using internal sound absorbing materials.
 
Flanking – The pathway along which sound travels around the perimeter or through holes within partitions or barriers erected to reduce the sound isolation between areas. Examples of flanking paths include ductwork, piping, back-to-back electrical boxes within partitions, window mullions, etc.
 
Free Field – Sound from an outdoor source where no obstructions exist.
 
Hearing Threshold Level (HTL) – Amount in decibels that a specified signal can exceed to cause damage to the ears of a listener.
 
Hertz (Hz) – Sound frequency expressed by cycles per second.

Insertion Loss – The reduction of sound power levels reached by inserting a muffler or silencer in an acoustic transmission system.
 
Live End/Dead End – An acoustical treatment plan for enclosed areas in which one end is highly absorbent while the other is reflective and diffusive.
 
Loudness – The strength of the physical resonance of a sound to sound pressure and intensity, as experienced by a listener.
 
Noise – A term referring to a sound of any kind, usually in reference to unintelligible or unwanted sound.
 
Noise Criteria (NC) – Sometimes referred to as “dBA levels,” it is used to assess listening conditions at ear level by gauging sound levels at loudest locations in a room.

Octave Band (OB) – A range of frequencies where the highest frequency of the band is double the lowest frefquency of the band.

Radiation – The process in which structure-borne vibrations are converted into airborne sound.
 
Reverberation – Sound waves that continue to bounce off surfaces after the source ends, until the sound waves lose energy and eventually die out.

Reverberation Room – A test chamber designed so that the reverberant sound field within the room has an intensity that should be the same in every direction and at every point. It is often used to measure transmission loss and sound absorption.

Sabin – The unit of measure used for sound absorption consisting of the number of square feet of sound absorbing material multiplied by the material absorption coefficient.
 
Septum – A thin layer of material sandwiched between two layers of absorptive material that prevents sound waves from passing through the absorptive material.

Sound – Pressure waves traveling through the air or in other elastic materials.

Sound Absorption – The acoustical process in which sound energy is dispelled as heat rather than reflected back to the environment as sound.

Sound Level Meter – An instrument used to measure sound pressure levels. Type 1 are precision instruments, whereas Type 2 are general purpose instruments.

Sound Power Level (Lw) – A measure of the total airborne acoustic power created by any noise source; it is expressed on a decibel scale referenced to a usual standard of 10-12 watts.

Sound Pressure Level (Lp) – A measure of air pressure changes caused by a sound wave and expressed on a decibel scale referenced to 20µPa.
 
Soundproofing – Creating an area insulated against noise.
 
Structure Borne Noise – The transmission of energy from vibrating structures or solids into noise.
 
Vibrations – Like those with structure borne noise, they are the wavering of a boundary that defines the motion of a mechanical system and can be reduced by isolators or damping.
 
Volume – Cubic area of a space calculated by the length x width x height of the space. Volume influences reverberation time.
 
Wavelength – Wavelike compressions and rarefaction produced by sound passing through air. Sound waves vary with frequency.