A critical part of architectural acoustics, reverberation, affects the way a space sounds. Whether a high or low rate of reverberation, a whole building can sound different, from muffled and claustrophobic, to loud and busy.
Reverberation also incorporates speech intelligibility, where dialogue or sound coming from a particular source becomes distorted or muddy due to the bouncing around of sound waves off of acoustically reflective surfaces.
Reverberation impacts people, whether working or living in a poorly designed space and is also reported to have psychological impacts. We will dig into those later on!
In this post, we will cover what reverberation is, why it matters, and how architects and designers can control it.
What is reverberation?
In any architectural environment, as sound is emitted in any form it takes time to dissipate. However long it takes for that single sound to become inaudible is what the reverberation time is.
Now, onto the science bit. There are many elements to a space that can increase or decrease the reverberation time. What prolongs the sound is how many times the sound wave can reflect off surfaces in the room. The more hard, shiny, flat surfaces in a space the more likely a longer reverberation time than a room that’s fluffy floor to ceiling.
As sound continues to reflect and reverberate, noise builds up. This is why reverberation in a room impacts speech intelligibility (understanding) and the quality of sound, due to the muffled and repeatedly bounced-around sound waves.
How does reverberation impact architectural acoustics?
Depending on what you want from your space, the ideal reverberation time, as well as other ideals for acoustics in general, will differ. For a space where you want clear speech you will want to aim for a low reverberation time (below a second) however for a concert hall or amphitheatre, a higher reverberation time will add depth and sumptuousness to the music.
For multi-functional spaces, it can be difficult to engineer the environment to cater for the reverberation time and acoustic quality needed in each section.
Long reverberation times in spaces that require high speech intelligibility, like boardrooms, classrooms or training spaces can become disastrous. At Sound Zero, we have encountered many projects where acoustic design and treatment has had to be retrofit because of this.
Take this example – a conference room with high reverberation means speech sounds muffled, so each person in the conference endeavours to project their voice further by speaking louder. This situation soon spirals, and it is made clear that the architectural acoustics of this space are not fit for purpose.
Examples such as those however can also miss another key impact of poor reverberation – the psychological impact.
Imagine you have just been to the cinema, then as the movie ends, the light comes up, and you make your way out of the theatre, you feel as if you have emerged from a different world.
This is due to the high levels of soundproofing in the cinema which makes the reverberation time extremely low. The sound is so deadened in there it can impact your sense of space and surroundings.
If you are in a working environment that is very quiet and has a very low reverberation rate, the same sort of experience can occur. It is reported that in these environments, people get tired quicker, and the space can seem dry and inhuman. That’s why it’s important to find a middle ground and a balance of good acoustic quality but not too much acoustic treatment.
Getting the right reverb time can leave people more energised, happy, and attached. This is why architects should follow key documents which state exactly the right reverberation time for each specific room of a building.
Why is it important to consult with an acoustic specialist?
Placing acoustic design and comfort at the forefront of your current and upcoming projects is more important than you might realise. Getting the acoustics right at the design and planning stage will save your project time and money, especially in the awful case you have to retrofit.
Collaborating with acoustic consultants will allow you to deliver a unique and effective project with high-quality architectural acoustics that masters the science of sound in your specific development.
If you are an architect or developer looking to achieve an improved acoustic environment in your next building project, then turn to Sound Zero, experts in design-led acoustics.
Our team of acoustic consultants is available to discuss your architectural acoustics needs to ensure you select the right acoustic treatment for the space you are working on. We have a range of products that can be completely customised to your colour, size, fabric, and other product requests.
Please do not hesitate to contact us today to go over our bespoke design-led acoustic solutions that can transform your architectural projects.