An Innovative Approach to Reverberation Time Measurement: Exploring the OIS as a Sustainable Alternative in the Brazilian Context

This research aims to compare different methods for measuring reverberation time in indoor environments based on the ABNT NBR ISO 3382-2:2017 standard. Two distinct methods will be analyzed: interrupted noise and impulse response, with the goal of investigating how the choice of noise source can influence the measurement results, considering a frequency range from 50 Hz to 5 kHz. In the interrupted noise method, an omnidirectional sound source emitting pink noise will be used, characterized by a constant energy distribution per octave frequency band. In the impulse response method, two sources will be evaluated: balloon pops, a traditional technique widely used in Brazil, and the "Origami Impulse Source" (OIS), developed by Toyoda et al. (2011), which uses the Japanese paper folding technique to generate characteristic impulsive noise resulting from a sudden movement. The research provided evidence that the OIS is an effective, sustainable alternative that is compatible with the Brazilian context, offering an innovative and easy-to-use method with similar characteristics to conventional sources. Differences in reverberation times are expected, which may underscore the importance of selecting the appropriate source for accurate measurements. A discussion will be provided on the practical relevance of these methods and the suitability of their applications.