This informal CPD article, ’Navigating complexity: designing sound systems for large-scale buildings’ was provided by Krzysztof Młudzik and Katarzyna Lenczewska of Ambient System, a European producer and provider of modern PA/VA solutions for the dynamically developing security communication and audio industries.
Imagine yourself in a busy, vast sport area or a bustling transportation hub, surrounded by the sounds of people and movement. Hidden speakers broadcast automated messages amidst the chatter and footsteps. Doors open and close, adding to the background noise, while the hum of the ventilation system provides a constant backdrop. But did you know that all these sounds were carefully planned for? Designers anticipate challenges like background noise and reverberation to ensure a pleasant auditory experience. Thanks to modern software, they can predict and plan sound systems long before they're installed, making sure everything sounds just right in these lively spaces.
Reverberation: The sonic battle of sound engineering
When making an acoustic simulation, the sound engineer will look into the loudspeaker coverage and predict the system sound pressure level output, allowing to ensure the adequate level of voice messages and sound-to-noise ratio. What is even more crucial is that the engineer can look into the acoustic parameters of the room itself – most importantly the Reverberation Time.
We often forget that not all rooms are acoustically workable. In some cases, a room is so susceptible to the creation of sound reflections, that no matter what loudspeakers we use, it shall not be possible to achieve fair speech intelligibility in that venue.
Reverberation is a natural phenomenon, where the presense of sound within a room causes the creation of reflected sound. Whenever a soundwave meets an obstacle such as a wall, ceiling, etc. part of the sound energy is reflected back into the room. For the human hearing this reflected sound is very much like noise, decreasing the perception of other sounds.
Technology – to the rescue
In this scenario the solution lies in advanced technology and sound analysis tools. In recent years, using acoustic calculation software has become the industry standard for designing PAVA (Public Address/Voice Alarm) systems. Such type of software allows to trace how soundwaves travel within a virtual 3d model of a room and accurately predicts critical acoustic parameters such as: Reverberation Time (RT), Sound Pressure Level (SPL) and speech intelligibility – described by objective parameters such as the STI and/or ALCons. Having this tool the engineer can quickly optimize the loudspeaker placement and if necessary, introduce sound absorbing materials to bring the room reverberation in check.
Minimizing costs and risks
PAVA systems have
to comply to specific acoustic requirements, concerning both SPL output
and speech intelligibility. Often when engineers discover a problem with
meeting these criteria it is already a late stage of the project execution,
where even simple solutions become problematic – cables are already in place,
loudspeakers have been installed in given positions and civil works are almost
at an end. To modify a loudspeaker setup or introduce acoustic treatment at
this stage is more cost full than planning it from the start. Furthermore – the
implementation of these solutions will take time and may threaten the project
execution schedule, potentially causing the contractors suffer damages for any
delay.
It is for these specific reasons that acoustic simulations should always be considered compulsory
for any type of project involving large scale architecture.
Acoustic simulations – predicting sound system performance
In the realm of large-scale building projects, the utilization of acoustic simulations is paramount for ensuring optimal sound system performance. Whether it's a transportation hub, office complex or an entertainment venue, the challenge remains consistent: designing sound systems that enhance rather than detract from the overall experience. Through the application of advanced computer software, engineers can anticipate and address potential acoustic hurdles early in the design phase. By fine-tuning parameters such as loudspeaker configurations, reverberation management and background noise mitigation, these simulations enable designers to create immersive auditory environments that prioritize safety, comfort and functionality. Acoustic simulations thus stand as an indispensable tool in the repertoire of building design, enriching the lives of occupants and visitors alike.
Silent hero of voice messages
In the intricate dance of construction and material obstacles within buildings, alongside the imperative of providing safety and communication through voice messages, acoustic simulation emerges as a powerful tool. It uncovers hidden challenges in PAVA systems early on, enabling swift adjustments to loudspeaker design and building layout. Without this foresight, issues would remain dormant, resulting in costly adjustments later. By employing acoustic simulations, we ensure the smooth operation of voice alarm systems, prioritizing safety and comfort in buildings.
We hope this article was helpful. For more information from Ambient System, please visit their CPD Member Directory page. Alternatively, you can go to the CPD Industry Hubs for more articles, courses and events relevant to your Continuing Professional Development requirements.
