Development of MIMO technique for 3D Auralization

The Sipario project has been created with the aim to virtually reconstruct 3D audio-video of artistical performances. To preserve the memory of the Opera and live venues, several historical Italian theatres have been assessed under an acoustic perspective based on Multiple Input Multiple Output (MIMO) technique. A prototype of loudspeaker and a multichannel microphone spherical array have been employed as the main instrumentation to determine the acoustic characteristics of these cultural heritage. The prototype of loudspeaker has been used by feeding the Exponential Sine Sweep (ESS) signal to all the 32 transducers while the microphone characterized by a 32channel spherical probe recorded the room impulse response (RIR). The utilization of this new generation of technology allows the assessment of a dynamic directivity pattern of any type of sound source, particularly referred to actors and singers moving onto the stage of the performing arts places. This paper introduces some mathematical framework for extracting any directivity of virtual microphones from real microphone array and of virtual sources from real loudspeaker.