The influence of noise on monaural room acoustic parameters utilizing different evaluation methods

Abstract

Besides clarity and definition, the reverberation time is the most common room acoustic parameter. The latter is also an essential quantity for acoustic measuring techniques (i.e. sound insulation, scattering or diffuse absorption). The unavoidable occurring noise in every measurement is the most significant factor that causes incorrect evaluated parameters. Therefore, it is important to respond to the effects caused by noise. In this study, different noise compensation methods are compared theoretically and based on measurements. At first all methods are investigated theoretically utilizing a simple parametric model impulse response. As a second step long-term measurements have been conducted in an auditorium to analyze the performance of the different techniques under realistic conditions. Therefore, the excitation signal has been varied in volume to obtain measurements with different noise levels and the evaluated room acoustic parameters are examined as a function of peak-signal to noise ratio. Theoretical and measured results coincide with each other for each analyzed method. The performances of the examined evaluation methods differ clearly. In particular, the three methods defined by ISO 3382 show different behaviors. The advantages and the limitations of each noise compensation method are presented. © 2013 Acoustical Society of America.