Measurement of car cabin binaural impulse responses and auralization via convolution

Abstract

Auralization is a well-known method used to create virtual acoustic scenarios. This work elaborates techniques for the Binaural Room Impulse Response (BRIR) extraction of the interior of a passenger car cabin. As a novelty, this study developed a binaural recorder based upon digital MEMS (micro-electro-mechanical system) microphones combined with an Arduino compatible microcontroller (Teensy). To improve the recordings, spectral corrections to the acquired data were carried out. The system is compact and cost-effective, creating an advantage for those measuring different source-receiver positions. For this paper, several combinations of BRIRs were tested, including combinations of binaural recordings for ambiance. Finally, equipped with the BRIRs database, it was possible to auralize different situations in real-time, for example, a conversation between two people (with the possibility to switch/tune background music and engine sound on and off). Furthermore, it was also possible to combine sources and receivers simultaneously with a contactless camera head tracker. Listening tests revealed that the spatial impression was preserved, rendering exceptional results as a virtual environment.