How does an acoustic silencer or sound trap work?

An acoustic silencer or sound trap works by absorbing, dissipating, or reflecting sound waves inside a casing. It is generally made of absorbent materials (high-density mineral wool, acoustic foam, air chambers, baffles) that convert sound energy into heat. The internal geometry allows for the treatment of different frequency bands while limiting pressure drop in the system.

When should an acoustic sound trap be used?

An acoustic sound trap is used whenever the noise level generated by an airflow or equipment becomes disruptive to operators, the neighborhood, or regulatory compliance. It is particularly recommended for ventilation systems, air handling units, HVAC systems, compressors, chillers, generator sets, blowers, and industrial process machinery.

How do I choose the right acoustic silencer for my installation?

The choice of acoustic silencer depends on several criteria: the sound level to be attenuated, dominant frequencies, network type (rectangular or circular), airflow rate, permissible pressure losses, temperature, environment (dust, humidity, corrosion), and space constraints. An acoustic and aerodynamic study helps define the type of silencer, its dimensions, and its target performance.

Can acoustic silencers be custom-made?

Yes, acoustic silencers and sound traps can be custom-made. At Écib, the dimensions, internal geometry, type of absorbent materials, and connection methods are adapted to each project to achieve the best compromise between acoustic attenuation, pressure losses, and integration into existing installations.

Are acoustic silencers effective at low frequencies?

Treating low frequencies is more complex, but certain types of silencers, such as reactive silencers or hybrid configurations, are specifically designed to improve attenuation in these frequency bands. The internal design, silencer length, and flow area are then dimensioned according to acoustic requirements and installation constraints.

Does an acoustic silencer require maintenance?

An acoustic silencer is a passive device with no moving parts. Therefore, it does not require heavy maintenance. However, periodic visual inspections are recommended to check the condition of the walls, baffles, and absorbent materials, especially in dusty environments or those subjected to harsh conditions.

What standards apply to the performance of sound traps and acoustic silencers?

The performance of sound traps and acoustic silencers is generally measured in accordance with ISO 7235, which defines test methods for determining acoustic attenuation and pressure losses. Requirements for final sound levels may also be linked to labor regulations, environmental prescriptions, or acoustic comfort charters for industrial sites.

Home > Acoustic Silencers & Sound Traps for Industry

Acoustic Silencers & Sound Traps for Industry: Noise Attenuation Solutions

Q: What is the difference between an acoustic silencer and a sound trap?

A sound trap is a specific category of acoustic silencer designed to attenuate noise in air handling systems (ventilation ducts, air networks, etc.). The term "acoustic silencer" is broader and encompasses different types of devices (rectangular with baffles, cylindrical, reactive, etc.) intended to reduce sound levels while allowing air or gas circulation.

In industrial settings, noise levels generated by airflows, machinery, and processes can quickly become a major source of disruption, leading to auditory fatigue, discomfort, decreased productivity, and regulatory risks.
At Écib, we design acoustic silencers, also known as sound traps, which effectively reduce these nuisances while ensuring optimal air or gas circulation in your facilities.

Our acoustic solutions for industry are suitable for ventilation systems, noisy industrial equipment, HVAC installations, generator sets, compressors, and all applications requiring effective acoustic treatment.

ALTAÏR’ stratis Baffle silencers

Composition

Galvanized steel

High-density mineral wool

Dimensions

H: 300 to 2000 mm
L: 300 to 2000 mm
Depth: 600 to 2000 mm

Custom-made

On-site installation

What is an Acoustic Silencer?

An acoustic silencer is a device designed to absorb and attenuate sound waves generated by airflow or industrial equipment. It effectively reduces the sound level transmitted through a duct, an air handling system, or a process line, thereby ensuring acoustic comfort and regulatory compliance.

An acoustic silencer typically consists of:

absorbent baffles made of high-density mineral wool
perforated internal walls to promote acoustic dissipation
reinforced casings to prevent vibrations
internal chambers optimized to absorb different frequency bands

It attenuates low, medium, and high frequencies, particularly those produced by fans, compressors, or industrial machinery.

What is an acoustic sound trap?

A sound trap (or noise attenuator) is a specific type of silencer, designed to reduce airflow noise or limit sound propagation within an air handling system or around noisy equipment.

It is an absorbent system:

rectangular with baffles
cylindrical (often used in ventilation)
reactive (for combustion engines or motors)

Its role is to trap sound waves within an absorbent volume, while allowing air to pass through with minimal pressure loss.

Sound traps are particularly used in:

ventilation and smoke extraction systems
industrial HVAC installations
compressors and refrigeration units
hoods, air handling units (AHU), VRV, heat pumps (PAC)
process machinery
industrial cabins

How does an acoustic silencer work?

Its operation is based on two complementary principles:

1️⃣ Acoustic absorption

Baffles made of mineral wool or absorbent materials capture sound energy and convert it into heat.
This mechanism is extremely effective for medium and high frequencies.

2️⃣ Resonance / Reflection

In certain models (reactive, cylindrical, internal chambers), the geometry is optimized to:

slow down the sound wave
cause desynchronization phenomena
reduce low frequencies, which are often the most difficult to treat

Reference Standard

The performance of a sound trap is measured according to ISO 7235, a standard used by premium manufacturers in the market.

Types of Silencers & Sound Traps Available

To meet all needs, Écib designs several families of acoustic silencers, inspired by the best practices in the industrial sector.

Rectangular baffle silencers

Ideal for:

building and industrial ventilation systems
AHUs
installations requiring significant attenuation

Features:

high-density absorbent baffles
galvanized steel frame
custom dimensions
low pressure drop
optimal efficiency for medium & high frequencies

Cylindrical silencers (or circular attenuators)

Recommended for:

circular duct systems
round ducts
industrial fans and motors

Advantages:

simple installation
wide range of diameters
excellent integration into existing systems
reinforced options for high temperatures

Reactive silencers

Particularly used for:

combustion engines
generator sets
high-pressure compressors
vacuum pumps

Highlights:

excellent low-frequency performance
reinforced construction
designed for high temperatures
versions with internal acoustic lining

Sound attenuators for intake and discharge

To reduce noise generated by:

fans
compressors
dust collection units
extraction systems

Acoustic grilles & louvers

For:

industrial facades
outdoor air intakes
quiet air exchange

Applications of ECIB acoustic silencers

Our solutions are designed to integrate into all industrial environments:

Ventilation and air conditioning

AHU / CMV / VRV
air handling units
high-pressure ventilation ducts

Industrial equipment and processes

air compressors
boosters
pumps and motors
turbines
chillers & cooling towers

Energy Equipment

generator sets
industrial boilers
heat exchangers

Enclosures and Technical Rooms

machining enclosures
acoustic enclosures
machine rooms

How to choose the right acoustic silencer?

1️⃣ Determine the sound level to attenuate

dB(A) level, dominant frequency, proximity to sensitive areas.

2️⃣ Identify the type of installation

Rectangular / circular / reactive / low temperature / high pressure.

3️⃣ Measure airflow constraints

airflow rate
flow velocity
acceptable pressure drops

4️⃣ Evaluate the environment

temperature
humidity
dust
corrosion

5️⃣ Check Standards & Performance

Compliance with ISO 7235, attenuation efficiency per frequency band.

FAQ: Acoustic Silencers & Sound Traps

What is the difference between an acoustic silencer and a sound trap?

A sound trap is a specific category of silencer, optimized to absorb sound waves in air handling systems. The term "acoustic silencer" is broader and includes other technologies (reactive, cylindrical, etc.).

How do you know which model to choose?

The selection depends on the initial sound level, airflow, dominant frequency, and type of installation. A preliminary acoustic analysis is recommended.

Can silencers be custom-made?

Yes. As with Écib, most models are custom-made to perfectly adapt to aerodynamic and acoustic requirements.

Do silencers reduce pressure drop?

Modern models are designed to offer low pressure drop while ensuring a high level of absorption.

In which environments should a sound trap be installed?

Ventilation, industry, generator sets, compressors, dust extraction, production machines, acoustic booths...

Are silencers effective at low frequencies?

Yes, provided reactive or hybrid models are used.

Do silencers require maintenance?

No, they are passive devices. A regular visual check is sufficient.

What are the applicable standards?

Acoustic performance is regulated by ISO 7235, commonly used in the industry.

Glossary of terms related to silencers and sound traps

Sound trap

An absorbing device integrated into a duct to reduce noise.