How many sound absorbers are needed for optimal acoustics?
Determining how many sound absorbers are needed in a room depends on several factors, such as the size of the room, its purpose, furnishing, and building materials. A well-balanced sound environment is about finding the right balance between sound absorption and reflection to reduce disturbing echo and create pleasant acoustics.
To achieve optimal sound dampening and improved speech intelligibility, a well-planned strategy is required where the right number and type of sound absorbers are used. Here we explain how to calculate the need for sound absorption and create an acoustically pleasant environment.
How do you determine the number of sound absorbers?
The exact number of sound absorbers depends on the specific characteristics of the room. Some of the most important factors to consider are:
Room size and shape
Larger rooms with high ceilings generally require more absorbers to reduce reverberation.
Building materials and surfaces
Hard materials like concrete, glass, and wood reflect sound more than soft materials.
Furnishing and decor
Furniture, carpets, and textiles affect acoustics and can contribute to some sound absorption.
Room usage
A conference room requires more sound-absorbing material than a living room to create a good conversation environment.
In general, it is recommended that 20–30% of the room's surface be covered with sound-absorbing material to achieve a balanced acoustic environment. This includes walls, ceilings, and sometimes even floors, depending on the room's acoustic needs.
Calculate reverberation time for an optimal sound environment
Reverberation time, that is, how long the sound bounces around in the room before it is dampened, is an important factor in determining how much sound absorption is required. A room with a long reverberation time can feel noisy and stressful, while a room with too short a reverberation time can feel muffled and unnatural.
Using an acoustic calculation tool, you can measure the current reverberation time and get a better idea of how many sound absorbers are needed to achieve an optimal sound environment.
Target reverberation time in different environments:
Offices & meeting rooms: 0.5–0.7 seconds
Classrooms & educational facilities: 0.6–0.8 seconds
Restaurants & cafés: 0.6–1.0 seconds
Home theaters & recording studios: 0.2–0.5 seconds
The longer the reverberation time, the more sound absorbers are needed to reduce sound levels and improve sound quality in the room.
Strategic placement of sound absorbers
To get the maximum effect from sound-absorbing materials, placement is crucial. Simply covering a large area without considering strategic positioning rarely yields optimal results.
Wall absorbers
Placed on surfaces where sound reflections are strongest, such as opposite walls in meeting rooms and offices.
Ceiling absorbers
Perfect for rooms with high ceilings or open-plan spaces where sound spreads freely.
Freestanding sound absorbers
Can be used in larger rooms or open offices to divide spaces and improve the sound environment.
Acoustic art panels
Combine design with function and can be placed in strategic locations to reduce reverberation.
By combining different types of sound absorbers and placing them where they make the biggest impact, you can achieve a balanced and pleasant sound environment without overusing materials.
How to create a pleasant sound environment
Installing sound absorbers is not only about reducing noise but also about creating an environment where speech intelligibility and acoustic comfort are improved. By analyzing the room’s size, reverberation time, and purpose, you can determine exactly how many absorbers are needed to achieve the desired result.