Acoustics in Learning Environments
Why do we still teach in echoey spaces?
We would never be expected to read in a classroom without light. We would never use a classroom with no heating, yet we often teach in spaces that make the sound of our voices blurred and difficult to understand.
Poor acoustics in a classroom has a direct and negative effect on the health and performance of both students and teachers. Detailed analysis has been carried out all over the world and the evidence is unanimous and irrefutable.
How do we learn?
The process of learning, for a child or young adult is all about making sense of the input that they receive. Over half of an average school day is spent listening, so to stand the best chance in life, we must ensure that the message being transmitted is actually received.
If the lights went out, the caretaker would be called in immediately to replace bulbs, yet studies suggest that 30% of learning takes place in an echoey space, and this is like teaching in the ‘acoustic dark’… They do not hear every word and then struggle to comprehend what is being taught. Why is that?
Children do not listen like adults...
Adults can have a conversation in a noisy environment and if we miss a word our developed brains draw on years of acquired knowledge and life experience to fill that gap and make sense of the sentence. Children and young adults by definition cannot. A study in America revealed that many students miss up to 1 in 4 words in classrooms with poor acoustics. That is like a telephone call that keeps cutting out. It is difficult and frustrating, and eventually we give up.
Is this the only problem with noisy classrooms?
Students are not the only people that suffer in echoey classrooms. Teachers are twice as likely to have vocal problems than most other professions. Having to raise a voice to combat noise build-up typically leads to a reduced vocabulary and expression dynamics, both significantly lowering student engagement. A recent survey of British classrooms showed that during interactive periods of classwork, noise levels regularly exceeded the ‘Exposure Limit Value’ of the Noise at Work Regulations.
And what are room acoustics?
Room acoustics describe how sound propagates in a closed space. Consider carefully these four facts:
- Once a sound is made it will get quieter further from the source.
- Sound will also bounce around the space until it is absorbed by artefacts in the room, causing you to re-hear it many times, milliseconds apart. This is called reverberation. It smears the sound, and the brain struggles to distinguish the primary and reverberant information.
- There is an inherent background noise level in every classroom, it is normally quite consistent; sounds from outside, the hum of a heater, the shuffling and the presence of 30 students. Reverberation adds another layer of unwanted noise.
- For the spoken word to be comfortably heard it should be significantly above background noise.
Look at this graphic before treatment: