Sound absorbing panels

In this page, you can find all the technical insights about the acoustic concept of sound absorption, the description of materials and technologies adopted to produce sound-absorbing panels and a detailed overview of their use in architecture and interior design.

For an immediate view of materials and sound-absorbing systems produced and sold by ACUSTICO® - The most various and complete online product catalogue of acoustic panels – we redirect you to our website page PRODUCTS.



Contents summary:

  • Sound-absorbing panels for architecture and interior design
  • Technical insights about the concept of sound absorption
  • Materials and technologies of sound absorbing panels


Sound absorbing panels (not to be confused with soundproofing panels) are meant for controlling the reverb inside confined and closed spaces.
In order to simplify the description, we can describe the acoustic phenomenon of reverberation with the common concepts of “rumble” and echo, intended as the prolonged stay of sound in a space.
Indeed, a sound emitted in a closed space can be heard amplified because of the reflections on ceiling and walls, especially if they are made of smooth and compact materials (acoustically defined as reflecting).
Reverb valour is generally expressed as RT60, which is the time (in seconds) a sound takes to reduce its intensity of 60 dB (decibel), or better the duration of the sound length.
This sound length duration is not exclusively determined by the surfaces features, but also connected to dimensions, shape and height of spaces.
The function of sound absorbing panels is to transform the reflective areas in acoustic sound-absorbing surfaces.
Sound-absorbing panels are generally made of foam and low-density materials, but can also be realized with compact perforated and milled wooden, metal or plastic sheets, associated to a sound absorbing layer: in this last case, the acoustic function is carried out by the sound absorbing material placed behind the aesthetic sheet.
Sound absorbers may be provided in the basic version or with coloured fabric covering, obtaining an acoustic material with additional aesthetic and design values.
Panel surfaces absorb most of the incident sound energy and reflect only a minimum quantity of it: this absorption capacity of the panel is defined by the so-called “sound absorbing coefficient”. It may vary according to the type of materials and their stratification, thickness, chemical composition, porosity, density, rigidity and shape.
Panels may be fixed to walls (permanent or removable installation), placed in adherence to the ceiling, suspended with cables as vertical baffles or in horizontal position, and they are also used in the movable free stand version. The installation of a proper number of panels can reduce the reverberation of any space drastically.
Acoustic panels can be singularly wall installed and, as an alternative, used to create a completely covered surface or a composition made of a number of elements. The installation of panels may be realized with glues (permanent position), or through hooks and brackets (movable position).

Sound-absorbing panels by ACUSTICO® can be divided in the following categories:

  • Sound absorbing panels with coloured fabric covering
  • Metal sound absorbing panels
  • Wooden sound absorbing panels
  • Sound absorbing panels made of synthetic expanded materials
  • Mirror sound absorbing panels


Sound absorbing panels with coloured fabric covering

ACUSTICO® proposes a wide range of panels available in many standard dimensions, covered with traditional or fireproof fabric, and offers the possibility to choose fabric type and colour from different collections.
Acoustic panels in the fabric-covering version are made with an internal polyester fibre core with variable thickness and density to improve the sound absorption performances. In this case, the fabric covering is just an aesthetic finishing, and does not modify any acoustic feature of the internal material.
If required, panels can be provided with removable fabric covering or with special internal reinforce structure, to give panels particular shapes or three-dimensional conformations, such as curves or waves (called “cloud panels”, as they are normally suspended to the ceiling).
Fabric-covered panels are available in many standard versions or, if requested, customized (shape, dimension, printing with photos or logos) and realized with specific acoustic performances.

Sound absorbing panels with coloured fabric covering


Metal sound absorbing panels

Metal perforated sound absorbing panels give spaces uniqueness, elegance and a strong hi-tech character. This panel line by ACUSTICO® is available in a wide range of perforations and may be realized with varnish steel, stainless steel or treated aluminium.
In addition to the standard perforations, ACUSTICO® can produce special false ceiling tiles, with specific millings and shapes, based on customer requests and drawings, using laser cutting systems.
Holes dimension and density define panels’ acoustic performances. Metal sound-absorbing panels are made with a coupled polyester fibre material, which contributes to improving sound absorbing features.

Metal sound absorbing panels


Wooden sound absorbing panels

Wooden acoustic panels ensure spaces prestige and an immediate feeling of warmth. ACUSTICO® wooden sound absorbing panels are available in a wide variety of wood essence and special finishes (lucid, brushed or coloured raw wood).
Holes dimension and density determine the acoustic and sound-absorbing performances of panels. Wooden sound absorbing panels are made with a coupled polyester fibre material, which increases the general sound absorption performances of these false ceiling tiles.

Wooden sound absorbing panels


Sound absorbing panels made of synthetic expanded materials

In the past, sound absorbing panels made of synthetic expanded materials (polyurethane and melamine) represented the sound absorbing panels par excellence, and were the only solution available on the market. This is confirmed by the fact that nowadays even the non-professionals perfectly know pyramidal panels, associating them to spaces for audio music.
In the last few years these materials lost a part of their commercial appeal and were replaced by panels realized with new components, for example polyester fibre. This last panel type grants a longer durability, gives better acoustic performances and meets more restrictive features of fire resistance.
ACUSTICO® produces many sound absorbers made with synthetic foam such as polyurethane, melamine and polyethylene, known with the commercial name of Resounder.
The possibility to produce and cut materials autonomously, together with their versatility and workability, permits to realize an infinite variety of shapes, dimensions and production solutions (even made according to a specific drawing provided by the customer).
Even for this type of products, ACUSTICO® only trades Italian certified materials of high quality and density.

Sound absorbing panels made of synthetic expanded materials


Mirror sound absorbing panels

Thinking about a sound-absorbing panel with a mirror surface may sound very strange. Indeed, a mirror is the most reflecting surface and absolutely not sound absorbing.
Actually it is not a real glass mirror, but a special sheet, stretched on its metallic frame; this panel covering is completely reflective from the visual point of view (panels seem to be real mirrors), but transparent to incident sound waves at the same time.
Essentially, incident sound waves are not reflected but absorbed by the coupled polyester fibre acoustic panel.

Mirror sound absorbing panels



Sound absorption is the material capacity to absorb sound energy and transform it into heat energy, and it’s variable from a material to another.
Sound-absorbing features of a material are higher when sound wave frequency increases (Frequency is the repetition of identical events in a specific time interval and is measured in Hertz).
A sound absorbing material should have simultaneously high “acoustic transparency”, a strong capacity of absorbing the entering air flux (low resistance to flux), and good “inflow energy dissipation” (high resistance to flux), so it should have the capacity of balancing these two contrasting features.
A porous material increases the dissipation of sound energy, because of the vibration of its surfaces and cavities (they are efficient at higher frequencies); instead, a compact material may be efficient at lower frequencies only if flexible, amortizing and damping the incident sound waves.
The absorption by porosity is a consequence of viscosity, and the sound absorbing capacity depends on the panel’s density and thickness.
Sound absorbing materials by porosity, can be divided in the following typologies:

  • Fibrous materials (such as glass wool, rock wool, wood shavings, cork, polyester fibres, gypsum, drywall, carpet, linoleum, curtains, natural and artificial fabrics of any type).
  • Open-cell materials (such as polyurethane foam, expanded polyurethane, melamine foam). 

Sound absorption by porosity is efficient at medium and medium-high frequencies, while it is necessary to adopt high thickness materials to reduce the sound energy at low frequencies.

Type of sound-absorbing materials

Fibrous sound absorbing materials

Glass wool
It’s a formless silicate material, derived from glass and marketed in rolls, slabs or sound absorbing panels, which has a high capacity of incorporating air through a fluffy structure and of transforming the sound wave in heat energy. For sure, it is one of the best sound absorbing materials, suitable for thermal insulation as well, relatively low-cost and highly efficient in the noise control.
Glass wool belongs to the family of synthetic vitreous fibres, as well as rock wool (described below). They are not so adopted for installation in spaces where sound-absorbing material is needed, since it’s not possible to understand which is the real dispersion of inhalable fibres and micro-dust in the environment, even if they are fabric-covered, film-covered or varnished. At the same time, the formaldehyde adopted in fibres ligands and present in this material is not traceable and measurable.

Rock wool
It is similar to glass wool and derives from a special extractive procedure of the volcanic rock. Its fire resistance is higher than glass wool. It’s available in panels and rolls.

In the past, cork was considered as the best sound absorbing material ever. Anytime the ecological and health exigencies have a fundamental role, and a higher economic budget is available, it is better to choose this type of acoustic material instead of glass and rock wool. It is available in slabs and sound absorbing panels.

Wood shavings
Wood shavings are realized through pressure and gluing of wooden fibres (deriving from working scraps) to form rigid and resistant panels. The result is a product with discrete sound absorbing and insulating properties. Even in this case, it is important to evaluate the quantity of formaldehyde present in the ligand adopted for the panel production.

They are artefacts made of natural materials (wood, linoleum, canvas, jute, coconut fibre) or acrylic-based. Carpets are commonly used for home and shopping stores furnishing, and contribute a lot in the achievement of acoustic comfort standards.

Curtains made of cloth or other natural/synthetic fabrics contribute in the absorption of sound waves, improving the reverberation features of sound for a better use of spaces.
Curtains can be acoustically more effective if they are thicker and heavier, considering the common sound frequencies of human speech.


Open-cells sound absorbing materials

Polyurethane foam
It’s a polymer with excellent acoustic absorbing features and it’s adopted both to fill in cavities (in order to grant walls better soundproofing performances) and to improve the acoustic comfort in living environments, civil and commercial buildings.
It’s suitable for different technical applications, according to its production versions (pyramidal foam, convoluted foam or smooth).
Produced with the shape of soft mattresses, polyurethane may be insufflated to fill in cavities and easily worked if used as polyurethane foam, answering to multiple sound absorbing necessities.

Expanded melamine
It’s a light and flexible sound-absorbing material, deriving from resins or acrylic foams, and it’s more fire resistant than expanded polyurethane, being a highly classified flame-retardant.

Expanded vermiculite
This mineral expands a lot if cooked and gains considerable soundproofing qualities. It’s adopted in case of insufflation or to realize sound absorbing plasters.

Expanded perlite
Silicate of volcanic origin, it can be used as acoustic insulator to fill in cavities or to realize sound absorbing plasters, in the same way as vermiculite.

Expanded clay
It’s a natural product, subject to high temperature cooking, for the realization of plasters and blocks with high sound absorbing qualities.

Other secondary acoustic absorbers are the expanded polyethylene and polystyrene (Styrofoam)