Whenever it is about imparting quality education to a child in a school environment, the things considered mostly are qualification and experience of the teachers, use of modern teaching aids, computers and audio visuals, the administrative staff and use of up to date and effective study books and materials. Another very important factor, which is almost neglected, is quality classroom acoustics. Most people would say: “is that even a thing?”. The most vital questions that must pop in everyone’s mind is, whether the student is able to hear clearly and understand whatever is taught in the classroom? On the other hand, is there any flaw in classroom design, which is exaggerating unnecessary noise?
It is always very difficult to hear lecture in a noisy environment. When a teacher or professor delivers a lecture in a classroom, the characteristic traits that a student catches is his unique voice and the subject content. The voice can tell a lot about a person such as his emotional state, intentions etc. and the subject matter discussed is always in proper order and structure. That is why quality acoustics in classroom is vey much necessary and should be the foremost priority. Special students such as the ones with hearing problems using aids and cochlear implants and in temporary situations when students suffer from cold and earaches, listening properly becomes all the more difficult in a noisy environment. A study suggests even normal students grab only one third of what is told in the classroom with high background noise. In a noisy room, the most expert teacher will also fail to deliver with his maximum efficiency. Students not native or fluent with the language being taught in the classroom also face difficult in grasping because of excessive noise. Thus, the teaching volume in the classroom must be louder than outside noise for clear understanding.
For creating good audibility in a classroom, the underlining cause of the noise should be identified first. The noise in the classroom can come from talking or walking in the hallway, traffic outside the school building, noise from the fans, windows or air conditioners (HVAC Systems) and their reverberations. To nullify all of the above factors, the structure and materials used in the classroom should be provide sound insulation as per the latest standards. For good acoustics, the walls and ceiling of the classroom needs to be fitted with sound absorbing materials ensuring sound-proof design. Auditoriums having sound amplifications needs to build far from the regular classrooms to avoid any disturbance. To get more information on acoustics topic one can pay to write essay and get a lot of relevant information on how everything should be organized in the classroom.
An educational classroom must meet all the standards and requirements to maintain good audibility. The students must be able to clearly perceive the speech or any other audio information in the classroom without the disturbance of any noise. This can only be achieved when the sound generated through speech does not get mixed with the noise along the path. Benjamin Boone is a famous specialist on acoustics. In one of his theses, he states that audibility in a classroom depends on:
- Classroom Shape;
- Sound-Proofing constructive solution;
- Size of the classroom;
- Sound source placement;
- Reverberation time.
A classroom having the shape of a rectangle or trapezoid provides good audibility with sound direction inline with the height. Whereas round, square, domes, oval or cylindrical shaped classrooms facilitating reflection of sound waves does not provide good acoustics. A lecture hall with rows of seats rising upwards as well as separated walls and ceilings just like an auditorium not only provides clear view but also good audibility.
Sound-Proofing Constructive Solutions
There are various sound-proofing solutions available with technological advancements to reduce noise in a classroom. Using non-reflective designs on walls and ceiling, wooden or man-made slabs greatly reduce noise. Air Conditioners or any HVAC Systems generating any king of noise must be placed in opposite direction to the path of sound i.e., the direction from speaker to the listener. High walls and long rooms do not provide good acoustics. Seats must be adequately spaced to ensure good audibility.
Size of the Classroom
The size of the classroom must be not very big and should not accommodate more than adequate students in normal speech scenario. According to study, the range of normal speech is approximately 20 – 30 m in its direction, 13 m on either side, 10 m on the back and 8 m above it. The strength of the classroom must also be adequate and in case of any arrangement of extra seats it must be positioned accordingly.
Sound source placement
The source ideally should be in front of a rigid wall for good acoustics. If the classroom is big enhancement devices for speech reproduction must be placed at adequate distances. If there are many speakers in the classroom, they must be present at the same place to provide good audibility to the students.
The speech when gets reflected through the walls generates an echo, this phenomenon is only called reverberation or attenuation of sound. The time between the speech and its reflection is called reverberation time. This time needs to be maintained at the minimum to avoid produce any disturbances or sound. To avoid such a situation, materials used on the walls and ceiling of the classroom must be either a good sound absorber or bad reflector. Usually porous materials with thin membranes provide quality acoustics in the classroom.
The importance of quality classroom acoustics must be given foremost importance in any decision making. Many standards are also implemented by the government to ensure quality acoustics in the classroom. Various efforts are always on the rise to stringent norms and provide better standards. Most importantly, it is the foremost duty of the school administrators, designers and parents to follow those norms and impart quality education to the child.