International Journal of Innovation and Scientific Research
ISSN 2351-8014 Vol. 17 No. 1 Aug. 2015, pp. 131-135
© 2015 Innovative Space of Scientific Research Journals
http://www.ijisr.issr-journals.org/
Corresponding Author: Aris A. Rusiana 131
Validation of Balloon Burst Method in Measurement of Reverberation Time
in a Classroom
Aris A. Rusiana, Joshua Marl C. Aves, and Kenje C. Hofileña
Basic Education Department,
Capitol University,
Cagayan de Oro City, Philippines
Copyright © 2015 ISSR Journals. This is an open access article distributed under the Creative Commons Attribution License,
which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
ABSTRACT: This paper aimed to validate the experimental result of reverberation time using balloon burst method with the
model (sabine equation) using AcMus software. The experimental procedure utilized dynamic microphone as the receiver,
balloon as the sound source and AUDACITY software to record and analyze the impulse created upon popping the balloon.
Balloon Burst method has a reverberation time value of 1.28s while the AcMus software gave a reverberation time value of
1.33s. The percent error was calculated and showed a 3.76% error. Hence, the balloon burst method can be used to
determine the reverberation time of a classroom also, it can be utilized as instructional materials in science classes.
KEYWORDS: Balloon burst method, reverberation time, Audacity, AcMus and dynamic microphone.
1 INTRODUCTION
Reverberation time measurement is very vital in improving the acoustics not only of classrooms but any other rooms. It
can strongly affect the learning of the students since it can interfere to the student and teacher interaction [1]. For auditoria,
it served as the basis whether it is for music playing or for speech. In theaters or opera houses, the rooms must be designed
in such a manner that every sit receives the acoustic quality that includes reverberation time. And in cinemas, to obtain an
outstanding quality of acoustics the reverberation time linear to the frequency must be aimed [2].
There are many methods that can be utilized to determine reverberation time this includes integrated impulse response
method, interrupted noise methods, filtered burst method implemented by Bruel & Kjaer and method of recording the room
response to an impulsive source. The first three methods mentioned in the latter statement utilized omni-directional
speakers which makes it expensive. The method of recording the room response to an impulsive source was preferred since
inexpensive sound source like balloon can be used. In addition, balloon is an omni-directional source and has a good spectral
content than other inexpensive impulsive sound source [3],[4]. Room response to an impulsive source was applied in the
study elsewhere using dynamic microphone, amplifier and speaker. Results showed good agreement with the conventional
sound level meter [5].
In this work, the balloon burst method was the preferred method. This method is a specific kind of method of recording
the room response to an impulsive source. Based on its name, the sound source used in this method is a balloon. Rusiana et
al. (2012) utilizes balloon burst method to determine the reverberation time for 3 classrooms. Same materials were used
with the current study applying sabine equation as the model. However, the reliability of the balloon burst method was not
tested. In this work, the reverberation time values were determined using the balloon burst method and compared with the
model sabine equation using AcMus software to avoid manual calculations.