Acoustic Problem: Sound reverberation

Reverberation noise is the one generated by the disturbance of the air that surrounds sound sources and is reflected on the surfaces of the room where the source is located, increasing the level of final noise.

This disturbance can come from a conversation between two people, music playing, television or any other source of noise, capable of transmitting through the air.

The energy created and received in a closed space can come from two ways: direct sound from the source to the receiver; and the reflected sound in the surfaces. This reflected sound amplifies the sound preassure level generated by the sournce increasing the reverberation tail.

The geometry of the room, its volume, its surface and the elements of decoration influence to aggravate or minimise the problem. Diminishing reverberation contributes significantly to increasing the acoustic comfort conditions of the enclosure, especially in crowded spaces such as hotels or restaurants. This cacoustic comfort increase is called Acoustic conditioning.

A reverberation problem is measured in time (of reverb), which measures the seconds that takes airborne noise in the room to fall below a certain level. The objective of the acoustic conditioning is to decrease this time using materials with absorbent properties that minimise the reverberation without having to modify the geometry of the space.

Consequences of reverberation sound

Reverberation creates problems, due to the increase in the final sound pressure, generated by reflections. These generated floating echoes increase the standing waves, decreasing the acoustic quality of the enclosure. Some of the consequences are:

• Sound pressure Increase: which increases the noise dose of workers exposed to this, having a detrimental effect to their health.
• Decrease in the concentration and performance of the workers in factories and offices.
• Decrease in the intelligibility of the word (RASTI / % Alcons) and capacity of understanding, something fundamental in schools, universities and conference halls.
• Decrease in the quality of musical sound in rehearsal rooms or auditoriums.

Solutions against reverberation sound

In virtually all cases, either a new work or a remodel, the only viable solution is to install acoustic sound-absorbing materials (dBcomfort HP, dBcomfort HP-Farbe, dBcomfort SCURE) to prevent the propagation of the enclosure’s reflections. To do this, the absorbent surface will be increased with porous materials until the reverberation time is suitable for the activity to be carried out:

1. dBcomfort HP

It is a sound-absorbing material based on an open cell melamine resin with a network of interlaced filaments. This fine three-dimensional structure, coupled with the high flexibility of the material gives it a high degree of acoustic absorption

The raw material (melanin) confers thermo-stability, with high chemical resistance to organic solvents and a wide range of acids and alkalines.

Its physical properties make it an ideal solution for acoustic absorption and thermal insulation in areas subject to demanding fire protection requirements; For example, in public buildings concurrence, cars, planes and trains.

It can be installed as decorative panels in offices, conference room, halls, lobbies, concert and exhibition halls, and recording studios. Because the raw material is flame retardant, it maintains its properties in a wide range of temperatures.

It is advisable to install dBsonic HP on suspended baffles because of its low weight particularly effective, for its greater exposed surface, to decrease the reverberating noise in factories, sports facilities or swimming pools.

dBcomfort in its color version, is finished with fireproof paint, applying a slight coat without penetration and without covering the pores, maintaining the absorbent properties of the material.

2. dBcomfot design: SCURE (Phono absorption and design at the service of people)

There are numerous alternatives of sound absorber materials, but only a few are developed aimed at people’s wellbeing. In addition to excellent sound absorption, the shape and finishes must be focused on habitable dwellings and have to comply with multiple environmental and building regulations.

Scure is born after years of research and understanding that absorption goes hand in hand with design. This is why SCURE was designed shaped to maximise sound absorption without losing the visual attraction and ease the installation has been developed.

The combination of important characteristics such as acoustic performance, fire behaviour and aesthetics result in a unique multi-layer material.

With the SCURE’s TF ® manufacturing technology, the acoustic corrections can be made easily, without work, in both new and existing spaces, in constructions as well as in refurbishments.

Design: Scure is the result of the joint development efforts of acoustic and material engineers, as well as interior designers. Its shape and size have been calculated to optimise its acoustic performance and offer a neutral design element capable of integrating and being compatible with any environment.

Conditioning: There is a wide range of sound absorbing materials, which offer absorption properties depending on the frequency, composition, thickness, coating and mounting method. However, few combine the advantages of each one of the materials as dBcomfort Scure does. In addition dBcomfort Scure adds a 3D geometric component which improves even more acoustic performance.

Noise problems are easily solved with Scure, decreasing the reverberation time, increasing the understanding between people, improving communication concentration and performance in spaces devoted to activities such as teaching or commerce

Sustainability: As with the rest of the dBcover, dBcomfort Scure solutions contribute to the improve the surroundings making the use of resources more efficient and reducing environmental impact to the maximum, both in the selection of raw materials as in the production process.

The TF® production method ensures a minimal production of CO2 in its manufacturing process, in addition to the use of recycled products and without the adhesion of harmful organic substances.

TF Multilayer Technology: TF® Technology is based on the multilayer composition of 3D-shaped materials. It combines fabric with the highest fire safety classification and acoustically permeable with state-of-the-art multilayer foam. This technology makes dBcomfort scure a unique element.

The composition of different densities and types of materials generates an optimal combination of thicknesses of different elasticity, porosity and tortuosity, for the volume of air enclosed, resulting in a selective absorption to the frequencies of interest which are to be attenuated.

dBcomfort SCURE unique surface geometry provides more effective area than a regular pannel, being a lightweight, small volume absorbent which is easy to install in any environment.

Materials: Trevira Cs® Polyester fabric allows the forming of a seamless piece, which confers a high dimensional high stability, protecting the inner padding.

Although the material seems visually very delicate, it is very resistant and difficult to damage or remove. Its high fire protection and a wide range of colours makes it a perfect covering for this use.

Fire protection: The multilayer composition made up of TF ® technology results in an ideal assembly of fire retardant elements against fire: B-s1, do.  The melamine has the peculiarity of not producing selfpropagating flames, so that in case of exposure to fire, it only produces a local consumption without emission of heat, preventing the possibility of a fire. In the event that the fire consumes the entire outer layer of the material, the inner nucleus is completely inert (class M0) so it would help curb the propagation of the fire. This is a desirable characteristic, which justifies the greater investment in those cases where security is an important factor or where the risk of flame could be considerable as in the case of building codes. Therefore this material serves as a measure of passive protection against fire.

Intelligent Absorption: The multi-absorbing element; With several layers, permits selective absorption, creating an impedance of opposition to the acoustic wave when a sound pressure is applied. In this way it acts on a wide range of frequencies focusing on the spoken word ones.

The material has been studied in such a way that its form generates a resonance at a close frequency of 500 Hz, this will create an absorption peak around this frequency.

This way, the normal deficiencies of regular porous materials that only perform in high frequencies can be covered.

Instalación: Measure/Calculate the reverberation time (contact the technical department of dBcover) to obtain the necessary Scure surface for optimum acoustic performance.

Consult our catalogs for more information about the solutions and technical data sheets: