Acoustic Characterization of Rooms Using Reverberation Time Estimation Based on Supervised Learning Algorithm

Abstract

The measurement of reverberation time is an essential procedure for the characterization of the acoustic performance of rooms. The values returned by these measurements allow us to predict how the sound will be transformed by the walls and furnishings of the rooms. The measurement of the reverberation time is not an easy procedure to carry out and requires the use of a space in an exclusive way. In fact, it is necessary to use instruments that reproduce a sound source and instruments for recording the response of the space. In this work, an automatic procedure for estimating the reverberation time based on the use of artificial neural networks was developed. Previously selected sounds were played, and joint sound recordings were made. The recorded sounds were processed with the extraction of characteristics, then they were labeled by associating to each sound the value of the reverberation time in octave bands of that specific room. The obtained dataset was used as input for the training of an algorithm based on artificial neural networks. The results returned by the predictive model suggest using this methodology to estimate the reverberation time of any closed space, using simple audio recordings without having to perform standard measurements or calculate the integration explicitly.

Noise Source Identification in Training Facilities and Gyms

“…Reverberation time measurements were conducted with use of an approximated impulse excitation in the form of a large balloon blast [20] at an unoccupied state. Due to the unusual case/type of enclosure and the preliminary nature of the investigations, a balloon blast was chosen instead of a Dodecahedron speaker due to the ease of use and successful application by other researchers [21][22][23][24]. Measurements at six points at the area of physical exercise led to a value of the average reverberation time t_60 [8,22,23] of 2.95 s. Measurements were conducted in six points, evenly distributed across the training venue.…”

Design Optimization of Three-Layered Metamaterial Acoustic Absorbers Based on PVC Reused Membrane and Metal Washers

“…The sound absorption depends greatly on the material, a correct choice will provide the most adequate absorption in all the frequency bands of interest [16]: Obtaining good sound absorption performance is not a simple thing; thus, several researchers are looking for new solutions to improve this performance. Recently, attention has been paid to a new category of acoustic absorbers based on metamaterials.…”