Conference_programme: 18.1 - Effect of room acoustics and noise on speech intelligibility and task performance in schools
Lecture: Good acoustics for teaching and learning
Author(s): Christensson Jonas
Summary:
It´s important that class rooms provide good speech intelligibility and speak comfort. Being able to listen without effort is important for learning and teaching, and we know that poor room acoustics is a burden that impedes learning and affect teacher voice health.\nA very good learning place is the Swedish forests where we can communicate over long distances without having to raise our voice. I have made several listening tests in the forest and also measured the sound reflections in different forests.\nThe results are interesting and I mean that “forest acoustics” should be the goal in terms of acoustic conditions in our schools.\nMany national sound standards put requirements on room acoustics in classrooms. One requirement is reverberation time, according to ISO 3382-2, and it´s often evaluated with T20. Unfortunately this is a very blunt measure, because we start T20 -evaluation first after the sound pressure level dropt 5 dB. This “waiting time” is often quite long and it´s a problem because we miss a lot of important information from the early part of the decay curve. \nA municipality in Sweden, Landskrona, wanted to improve the acoustics in their schools so they investigated the sound environment in their school buildings. \nIn Sweden we have a sound standard, SS 25268, where we put requirement on the sound environment. In some class rooms in Landskrona the reverberation time fulfilled the best sound class according to SS 25268, but the teachers complained about “bad” room acoustics.\nThe T20 measurement is evaluated by the “late” part of the decay curve. \nBy measuring Clarity C50 according to ISO 3382-1 we measure all reflections, and evaluate the balance between the “early” and “late” reflections. Therefor I mean we have to add C50 to control if the room acoustics is good enough for teaching.
Corresponding author
Name: Mr Jonas Christensson
e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.
Country: Sweden
