Repeatability of the balloon pop as a sound source in a room

High intensity and robust test signals are required to be produced by sound sources for acoustic characterisation and evaluation of different types indoor spaces. A range of sound sources are used in the industry and in research to generate impulsive sounds to excite acoustically a space and obtain its response to that excitation. The air-filled (party) balloon pop is a type of sound source widely employed for producing impulsive sound excitations. The popularity of this source is owed to its many convenient and practical merits. However there is limited information in the literature reporting the suitability and reliability of this source as a way to obtain room acoustics parameters. The aim of this study is to determine and assess the repeatability of results from impulse responses obtained from air-filled party balloon bursts as employed in field room acoustics testing. Repeatability is evaluated based on the standard deviation (σ) values from sound pressure peak levels of SPL (Lpeak), spectral distribution and Reverberation Time (RT30) measurements obtained from bursts of two common balloon sizes samples in a 170m³ room. Results showed a relatively high repeatability independent of the balloon size, when evaluated on Lpeak, spectral distribution and RT30 parameters. This study will inform practitioners on the level of reliability and suitability of the balloon pop as a sound source when selecting methods for obtaining room acoustics parameters.