Uncertainties of room acoustics simulation due to directivity data of musical instruments

ACCOLTI, ERNESTO; GIMENEZ, JAVIER; VORLÄNDER, MICHAEL

IEEE/ACM Transactions on Audio, Speech and Language Processing

IEEE

Año: 2023 vol. 32 p. 300 - 309

2329-9290

The directional index of sound sources such as musical instruments is an important input for the current methodsof room acoustics simulations. In this article, the uncertaintyof the directional factor of musical instruments for each bandis analyzed. First, the directional factors in third octave bandsare estimated from a dataset of measurements obtained with amicrophones array [S. Weinzierl et al., A Dataset of AnechoicMicrophone Array Measurements of Musical Instruments, De-positOnce Repository, 2017]. Then, different methods to estimatethe directional factor in third octave bands are analyzed, of whichthe method of averaging directional indices is selected due toits lower uncertainty and main error. Finally, the uncertaintypropagation due to the selected method is studied based onpredictions of time varying sound pressure level and dynamicloudness in a concert hall simulated by geometrical acoustics(GA) methods. About 50000 tones are simulated and its timevarying sound level and loudness are calculated in order toevaluate its uncertainty at the audience due to the uncertainty onthe input parameter source direcivity. The effects of source andreceiver positions and instruments are shown through probabilitydensity function estimations of the sound level differences andexcess loudness ratios between usual and control situations.About 50% of the studied data shows sound level differencesclose to±5dB and loudness excess ratio close to about±35%