Professional soundproof booths: mountings with silent blocks and multi-layer insulation

Decoupled fixings: structural stability and vibration control

In a soundproof booth, acoustic performance does not depend solely on the mass of its walls. It is also essential to control how the different components are connected and how vibrational energy is transmitted through the structure.

Since its inception, DEMVOX has developed its own solutions for sound insulation, modularity and structural decoupling, which have established it as a world-leading brand in the design and manufacture of professional soundproof booths.

For this reason, DEMVOX uses a system of precision mechanical fastenings combined with silent blocks and resilient elements. This solution ensures a firm and stable structure, whilst limiting the direct transmission of vibrations between its various components.

The screw provides pressure, strength and geometric stability. The silent block acts as a decoupling element, absorbing and reducing some of the mechanical energy before it can be transmitted to the next layer.

Consequently, the fixings do not act as a simple rigid joint between panels, but rather as part of a structural system specifically designed to control sound transmission.

The bolt as a structural precision component

A soundproof cabin must maintain precise dimensions in order to ensure the correct pressure on the seals, the alignment of the modules and the overall airtightness of the assembly.

Mechanical fastenings allow for precise control of the pressure applied at each joint, preventing displacement, play and unwanted movement between the parts.

This stability is particularly important in components such as:

• joints between modules;
• joints between walls, floors and ceilings;
• door and window frames;
• floating internal structures;
• zoom-in and zoom-out systems;
• points subject to loads or vibrations.

The precision of the joints helps ensure that the cabin retains its structural and acoustic properties after repeated assembly, relocation or modifications.

Decoupling using silent blocks

Silent blocks are components made from resilient materials capable of deforming in a controlled manner when subjected to vibration.

Their function is to reduce the transmission of mechanical energy between the different parts of the cabin. Rather than allowing rigid, direct contact, they introduce an elastic discontinuity into the vibration path.

When a sound wave causes one of the layers to vibrate, the silent block limits the amount of movement transmitted to the next structure. Part of that energy is absorbed and dissipated through the internal deformation of the resilient material.

The result is a connection that combines two fundamental properties:

• structural strength and stability;
• reduction in vibration transmission.

This combination ensures that the cabin remains firmly assembled without compromising the decoupling between its different structural levels.

Separate structural layers

DEMVOX systems consist of different layers that perform specific acoustic and structural functions.

Depending on the model, an outer structure, an intermediate structure and a floating inner structure can be combined, together with chambers, absorbent materials and elements of different masses and densities.

These layers do not function as a single, homogeneous wall. They are connected by anti-vibration mounts, silent blocks and mounting solutions that reduce rigid contact between them.

This configuration means that the sound energy has to pass through the following in succession:

• different doughs;
• intermediate chambers;
• materials of different densities;
• resilient connections;
• changes in mechanical impedance.

Each transition hinders the propagation of the vibration and helps to reduce the energy transmitted either outwards or inwards from the cabin.

Resonance control

Each material and each layer exhibits different vibrational behaviour. When structures are properly decoupled, vibrations from one layer are not transmitted immediately and uniformly to the rest of the building envelope.

This allows for better control of structural resonances and prevents the entire wall from behaving as a single vibrating surface.

The multi-layer design combines mass, separation, elasticity and damping to operate across a wider frequency range.

This principle is particularly important at low and mid-range frequencies, where structural transmission and the resonances of the assembly can significantly affect the final insulation performance.

Stability after each assembly

The modularity of a cabin is not simply a matter of being able to dismantle it. It also means that it can be reassembled whilst maintaining its alignment, rigidity, airtightness and acoustic performance.

DEMVOX fasteners are designed for use at specific, controlled connection points. This makes it easier for each component to return to its correct position and for the joints to regain the necessary pressure following reinstallation.

The system allows you to:

• remove and refit the cab;
• move it to a new location;
• enlarge or reduce its dimensions;
• replace specific elements;
• adjust the interior settings;
• to maintain the accuracy of the assembly.

The structure does not depend solely on the weight of the modules or the pressure generated between the components. The fixings actively secure the position of each component.

A structure designed to bear loads

Mechanical fixings also provide greater load-bearing capacity for components integrated into or fitted onto the cabin.

These may include:

• soundproof doors;
• viewers and windows;
• ventilation systems;
• interior panels;
• tables and stands;
• screens;
• technical equipment;
• electrical installations;
• wall-mounted fittings.

The load is distributed across an assembled and controlled structure, reducing the risk of displacement or misalignment.

This robustness is particularly important in large booths, professional studios and structures that need to support complex installations over long periods of time.

Insulation, stability and modularity

An acoustically optimised fastening should not be assessed solely on the basis of its ability to join two parts. It must be analysed as part of the overall behaviour of the cabin.

The DEMVOX mounting system allows you to integrate:

• controlled pressure on the joints;
• dimensional stability;
• structural strength;
• vibration isolation;
• separate structural layers;
• removal and reinstallation;
• enlarging and reducing the cabin;
• capacity to support equipment.

The final acoustic performance depends on the whole system: mass, chambers, airtightness, doors, windows, ventilation, flooring, ceiling, joints and the quality of the installation.

For this reason, the screw is not merely a mounting component. When combined with silent blocks, anti-vibration mounts and floating structures, it becomes an essential part of a robust, precise and decoupled acoustic architecture.

In DEMVOX, the fastenings ensure that the structure retains its strength and geometry, whilst the resilient elements control the transmission of vibrations between the different layers.

The result is a high-performance modular system, developed and refined over many years, which has helped to establish DEMVOX as an international benchmark brand in professional soundproofing solutions, designed to maintain sound insulation, stability and adaptability throughout the booth’s service life.