NEW METHOD FOR AURALIZING THE RESULTS OF ROOM ACOUSTICS SIMULATIONS

The results of most room acoustics simulation codes are usually energetic reflectograms with limited time resolution (usually 1ms or worst) and frequency resolution (typically octave bands, in a few cases 1/3 octave bands). When these results are employed for auralization, it is necessary to derive a set of high resolution impulse responses, providing narrow time/frequency detail, and containing spatial information (Binaural or Ambisonics). A novel process for creating these hi-res impulse responses is described, making use of sine-bursts synthesis (a sort of wavelet synthesis). For each octave band and each time slot, a number of sinusoidal bursts are generated. The time-domain envelope of these bursts is properly shaped and overlapped, so that they merge smoothly. Their amplitude is modulated in such a way that the computed energetic parameters (T60, Clarity, etc.) are perfectly reconstructed. For binaural rendering, each tone burst is convolved with the HRTF corresponding to the arrival direction. For Ambisonics rendering, each tome burst is copied on all the channels, with gains derived by the Ambisonics encoding formulas corresponding to the direction-of-arrival. Blind listening tests performed in a special listening room demonstrated that the new auralization technique outperforms the previously employed one, which was based on octave-band filtered noise bursts instead of multiple wavelets