s|TWIST| DUCT SILENCERS
Effective Noise Reduction for Ventilation and Ducts
Silencions s|TWIST| is a compact acoustic silencer that you can insert directly into the ventilation duct, without taking up any external space. The s|TWIST| silencer effectively reduces noise by up to 20 dB (even at low frequencies) and does not obstruct airflow. Discover s|TWIST| silencers and enjoy the peace and quiet you’ve been waiting for.


s|TWIST|: COMPACT SOUND ATTENUATORS
Compact silencers for ventilation
The Silencions s|TWIST| is a sound attenuator with dimensions and weight unmatched by other solutions on the market. It was designed for silencing ventilation systems and other air ducts. Its high performance stems from the use of acoustic metamaterials, enabling a level of noise reduction previously unattainable for such a compact size and weight. Thanks to its small dimensions and modular design, the s|TWIST| ensures seamless integration with any installation.
The Secret Behind s|TWIST|’s High Performance
Unique Geometry and Acoustic Metamaterials
s|TWIST| sound attenuators owe their effectiveness to a unique internal geometry and the use of acoustic metamaterials. These advanced structures enable a level of noise reduction far exceeding standard materials like perforated sheet metal or mineral wool. It is the geometry that defines their acoustic properties, not the raw material itself.
The modular design allows the attenuators to be connected, both to each other and to other acoustic solutions used in ventilation. Their attenuation effects are cumulative. Each subsequent attenuator delivers greater sound reduction or extends its effective range (broadband performance).




Sound Attenuators Made from a Durable Polymer
Durability, Resistance, and Easy Maintenance
The s|TWIST| attenuator is made from a robust polymer material, resistant to moisture, grease, contaminants, and temperatures up to 90°C. We can customize the housing and insert material to meet project requirements (e.g., to achieve enhanced chemical resistance).
Unlike attenuators that use mineral wool, s|TWIST| contains no absorbent materials. It ensures stable performance in varying environmental conditions and requires no replacement of its filling. This also translates into exceptionally easy maintenance, limited to periodic cleaning and disinfection. For easy cleaning, the attenuator is completely dishwasher-safe.
Effortless Installation, Superior Performance
An In-House Sound Attenuator Design
Installing the attenuator is exceptionally simple and intuitive. It can be easily retrofitted into an existing system without the need for dismantling or reconstruction. Furthermore, a perfect seal between the duct walls and the attenuator is not required, which eliminates the need to fill in any irregularities.
The s|TWIST| sound attenuator is an in-house design, developed by our acousticians. It performs perfectly not only as a standalone attenuator but also to complement standard acoustic attenuators. It enhances their performance in the low-frequency range—the most challenging range for traditional absorption-based silencers.


Lab-Tested and Confirmed Noise Reduction
Superior to Conventional Solutions
Silencions s|TWIST| sound attenuators effectively reduce noise propagating through ventilation systems and various types of ducts across a wide frequency range. They vastly exceed the performance of traditional solutions like ventilation grilles and covers. The efficacy of our solution has been verified by laboratory tests conducted in accordance with the ASTM E2611-09 standard. A sample measurement result is shown in Figure 3. We can custom-engineer the attenuators for a specific noise source and to meet installation requirements.
Key Features & Benefits of s|TWIST| Acoustic Silencers

Reduces noise by up to 20 dB
Effectively eliminates intrusive sounds within a targeted frequency range (200 – 3000 Hz).

Unobstructed Airflow
Maintains full ventilation efficiency without any restriction.

Customizable Configuration
Precision frequency tuning. Adapts easily to different duct diameters and shapes.

Ultra-Compact Profile (30-150mm)
Its compact design and a weight of under 100 g make installation easy, even in tight spaces with limited access.

Durable and Weather-Resistant
Built with materials that resist moisture and varying temperatures, guaranteeing a long product lifespan.

Modular Design
The modular construction enables multiple attenuators to be combined, providing excellent system flexibility and a cumulative silencing effect.
s|TWIST| ATTENUATOR MODELS AND CONFIGURATION
Below are the standard models of our s|TWIST| attenuators. They come ready-to-install and are equipped with mounting rings and clips for easy installation. Our sound attenuators can be customized for different diameters and shapes to match your ventilation duct specifications.

CUSTOM-ENGINEERED s|TWIST| ATTENUATORS
SOLUTIONS BUILT FOR YOU
Looking for a unique size or shape? We provide a complete customization service, from manufacturing rectangular attenuators to using specialized flame-retardant and self-extinguishing materials. Get in touch with us to discuss your project’s specific requirements.

APPLICATIONS FOR s|TWIST| SOUND ATTENUATORS
s|TWIST| sound attenuators are the ideal solution wherever intrusive noise from ventilation, air conditioning, or heat recovery systems is a problem. They are particularly effective in:
- Residential Buildings: ensuring peace and comfort by eliminating noise from HVAC and heat recovery systems.
- Hotels and Leisure Facilities: guaranteeing a quiet, relaxing environment for guests, free from ventilation system noise.
- Schools and Educational Institutions: improving conditions for learning and concentration by minimizing additional sources of noise.
- Hospitals and Healthcare: fostering a calm environment essential for patient recovery and focused medical work.
- Restaurants and Retail: creating a pleasant customer atmosphere, undisturbed by intrusive ventilation hum.
- Specific Industrial Environments: thanks to their resistance to moisture, grease, and contaminants, as well as their ease of cleaning, s|TWIST| can be used in selected industrial applications with harsh environmental conditions.
EXAPMLE APPLICATIONS OF s|TWIST| SOUND ATTENUATORS

Silencing Ventilation Grilles
Use s|TWIST| attenuators to replace or supplement your standard ventilation grilles. They deliver a major improvement in a room’s acoustic comfort without compromising the system’s airflow or aesthetics. Perfect for situations where you can hear neighbors through the vents or wish to silence noise in a restroom.
Silencing Vents in Doors and Walls
Ventilation openings in doors and walls significantly weaken the acoustic insulation of the entire structure. Without proper acoustic treatment, they become a source of noise. s|TWIST| attenuators effectively solve this problem. They reduce sounds transmitted through the openings while ensuring free air circulation. The entire structure gains better insulation performance, which helps create quiet and comfortable spaces in offices, hotels, and residential buildings.


Noise Control for Ventilation Terminals
Air intakes and outlets are common noise sources in any building, and the ductwork often transmits sound between separate rooms. Thanks to its small size and tunable performance, the s|TWIST| attenuator can be installed directly inside a duct’s inlet or outlet. This results in a significant reduction in transmitted noise with no impact on airflow efficiency or aesthetics. The silencer can be fitted at both the inlet and outlet of the duct.
Use in Machine Housings & Control Cabinets
Industrial equipment and ventilation often produce noise levels that violate safety standards. We custom-tune s|TWIST| attenuators to target the specific noise profile of your machinery. They can be installed directly inside machine housings or within the ductwork on your factory floor.
Their compact, absorption-free design ensures reliability and easy cleaning, even in demanding environments. This leads to quieter operations, which is essential for improving safety, boosting productivity, and ensuring compliance with strict acoustic regulations.

s|TWIST| SOUND ATTENUATORS VS. CONVENTIONAL SOLUTIONS: A COMPARISON

Frequently Asked Questions (FAQ)
This section answers the most common questions regarding Silencions s|TWIST| sound attenuators. Should you not find the information you require, please do not hesitate to contact us. We will gladly provide any further details.
Yes. Like any component installed in a duct, s|TWIST| silencers affect air flow in ventilation systems. However, the absence of absorbent materials in the silencer means that air resistance is significantly lower than in standard absorption silencers.
s|TWIST| silencers have many applications. They can be used to reduce noise in ventilation systems, openings and passages in doors and walls (e.g. in bathroom doors), as well as industrial equipment. If you have a specific problem and are wondering whether s|TWIST| would be a good solution, please write to us at contact@silencions.com.
Yes. We can manufacture acoustic silencers in non-standard shapes to match the cross-section of the opening or ventilation duct. It is possible to design a s|TWIST| silencer for a specific noise source – we can adjust the silencer’s range of operation to the characteristics of the noise source. Write to us at contact@silencions.com and tell us what kind of silencer you need.
s|TWIST| silencers are made of PLA or PA12 plastic, which makes them resistant to moisture, grease, dirt and temperature (up to 90∘C). Their durable construction and lack of absorbent material filling guarantee a long and reliable service life.
The s|TWIST| silencer is made using 3D printing technology from durable PLA or PA12 plastic. The materials we use to manufacture silencers are resistant to moisture, grease, contamination and temperatures up to 90∘C. The silencer is easy to clean and maintain, and thanks to the use of 3D printing, we can easily and inexpensively adapt the geometry of the silencer to the problem.
Contact Us
Don’t let noise compromise your comfort. Our team of expert acoustic engineers is here to help you choose the perfect attenuator for your specific needs.
We specialize in diagnosing and solving complex noise and vibration issues, creating innovative acoustic solutions for the most demanding applications.
Our business hours are Monday to Friday, 9:00 AM – 5:00 PM.
Phone: +48 881 024 855
E-mail: contact@silencions.com