NOISE
CONTROL
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General Considerations | Noise control may be accomplished through a variety of methods, which depend on the needs and limitations of the environment. |
Passive
Controls |
Passive controls include: dissipative absorption materials (porous materials) and structures (isolators, vibration damping), reactive devices (acoustic resonators) and structures (mechanical resonators), and barriers (walls, enclosures). |
Active Controls | Active controls include the computerized control of noise and vibration levels. |
Duct
Acoustics
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Duct acoustic treatments include both active and passive methods. Passive methods are commonly used for attenuation in the mid-frequency range. Active methods are used for higher attenuations at lower frequencies. Combined methods may be used for broad frequency, large attenuation needs. |