Acoustics is more often considered a niche subject than the other physical aspects of interior comfort. Maybe this is why assumptions and preconseptions guide the way in which people tend to deal with the sound quality of the interior environment. In India where I’m from, I’m frequently confronted by several presumptions or myths when I meet specifiers and the users of interior spaces. In this post I will aim to dispell three of the most commonly occuring.
Before we delve more into these myths, let’s first agree on the meaning of the word itself— A Myth is a widely held but false belief or idea. And that is exactly why it is important to bust it!
Myth 1: ‘There is no great difference between 0.7 and 0.9 NRC performance’
Though on absolute terms it is just a difference of 0.2 NRC value, it’s a great deal in terms of overall reduction in sound energy (the ambient noise) and reverberation time, for a given room. In a typical scenario, a ceiling area or one wall surface will still consist of only about 17% of the space. And when it is to be cladded with an absorber, the thicker the better – always!
Like it is shown in the graph above, the higher the absorption coefficient, the greater the reflex reduction in sound pressure levels and this actually goes much steeper post 0.7 values.
Myth 2: ‘High performance acoustic treatment is usually difficult to justify in the given budget’
In a longer run, with expected increase in the level of output and productivity from the users of the space, the capital expenditure involved in improving acoustic quality, can be justified indeed along with the reduced cost of running the business and the premises.
This is best illustrated in a recent study conducted in collaboration with the Stress Research Institute in Stockholm, which correlates Acoustic Conditions and User Productivity
Myth 3: ‘A high performance acoustic ceiling is enough for better acoustics’
To achieve ideal room acoustics usually requires analysis of the room dimensions, the people occupying the space and the activity involved; not just from the perspective of an acoustic ceiling but also other surfaces like the four walls, furniture, flooring area, etc.
In premises where there is a need for higher acoustic performance due to special activities, sound absorbing wall panels in combination with a fully covering suspended ceiling are often necessary to meet the acoustic requirements.
Especially in open office areas, it is highly recommended to also focus on the immediate furniture set-up. This is because when someone is talking at desk level; either over phone or to the colleague beside him or her; most sound waves first hit the immediate furniture screen and if that is made as absorptive as possible then it can surely contribute to reducing overall disturbance to the office users. More clarity can be sought on this subject on this video link.
What are some common myths about acoustics in your country?
Please feel free to add your thoughts in the comments section below!