Optimizing meeting room acoustics: A practical guide

Meeting room acoustics are often overlooked during workspace design. Yet, they play a crucial role in the comfort and effectiveness of meetings, especially those involving video conferences.

This article guides you through key concepts and best practices to optimize your meeting room’s acoustics.

Contents

The importance of meeting room acoustics

The acoustics of a room directly influence communication clarity and participant fatigue. In a meeting room, where verbal exchanges are constant, good acoustics are essential for ensuring comprehension and reducing the effort needed to concentrate.

Poor acoustics can lead to echoes, excessive reverberation, and disruptive background noise, making conversations difficult to follow and increasing auditory fatigue.

Soundproofing vs. Acoustics: Understanding the difference

Acoustics and soundproofing are often confused but serve distinct purposes. Acoustics focus on sound quality within a room, emphasizing communication clarity and auditory comfort. Soundproofing, on the other hand, aims to prevent sound from entering or leaving a space. It focuses on sound insulation to protect the room from external noise and vice versa. Combining these two approaches can create meeting spaces that are both pleasant for internal communication and shielded from external interferences.

Acoustic fundamentals

Reverberation Time (RT60)

Reverberation time is the duration it takes for sound to decay by 60 dB after the sound source stops. High values lead to excessive reverberation, making speech difficult to understand.

Reverberation time varies depending on the room’s use and size:

Room Type	Volume	Recommended RT60
Recording studio	< 50 m³	0.3 s
Classroom	< 200 m³	0.4 – 0.6 s
Office	< 1 000 m³	0.5 – 1.1 s
Concert Hall	< 20 000 m³	1.4 – 2.0 s

> An optimal RT60 for a meeting room is between 0.6 and 0.8 seconds.

Sound Isolation

Sound insulation aims to prevent sound from passing through the walls of a room. It is measured by the sound reduction index (Rw), expressed in decibels (dB). For a meeting room, an Rw of 45 dB or more is recommended to ensure confidentiality and avoid external disturbances.

Background noise level

The background noise level should be low enough not to interfere with verbal communication. A background noise level below 35 dB(A) is ideal for a meeting room.

Soundproofing a meeting room: Solutions

Soundproofing a meeting room requires a holistic approach, combining various techniques and materials to both absorb and isolate sound. Here are some recommendations:

Absorptive materials

Acoustic panels: Install panels on walls and ceilings to absorb sound and reduce echoes.
Micro-perforated ceiling tiles: Effective at reducing reverberation and can be discreetly integrated into the room’s design.
Curtains or blinds over glass surfaces: Prevent sound reflections on hard surfaces.

Sound insulation

Acoustic partitions: Use partitions with a sound transmission loss (Rw) of at least 30-40 dB.
Asymmetrical double glazing: Prefer reinforced glazing or PVB layers for better sound insulation compared to single glazing.

Background noise control

Quiet HVAC systems: Choose heating and cooling equipment with low noise levels.
Equipment placement: Keep noise sources away from primary discussion areas.

Interactions Between AV Equipment and Acoustics

Strategic placement

The placement of audiovisual equipment must be carefully planned to maximize acoustic efficiency:

Microphones: Place microphones away from noise sources (like HVAC systems) and reflective surfaces (like windows and bare walls).
Speakers: Position speakers to avoid acoustic dead spots and minimize interference between direct and reflected sound waves.

Calibration and tuning

Equalization (EQ): Adjust EQ settings to compensate for the room’s acoustic characteristics, boosting or cutting certain frequencies for balanced sound.
Level Adjustment: Ensure microphone and speaker volume levels are properly balanced to avoid distortion and feedback.

The importance of an acoustic study for meeting rooms

An acoustic study is a crucial investment for any meeting room. It helps identify potential acoustic issues and proposes effective solutions to address them. An acoustic study includes:

Analyzing existing conditions

Precise measurement tools, such as sound level meters and spectrum analyzers, are used to gather data on RT60, background noise levels, and sound insulation.

Acoustic modeling

Collected data is then used to create acoustic models of the room. Specialized software simulates the impact of various material configurations and layouts. This modeling helps predict the room’s acoustic performance after implementing the proposed solutions.