Perceptually Motivated 3D Diffuse Field Upmixing

This paper presents a novel 2D to 3D diffuse-field upmixing method developed based on two recent psychoacoustic studies on vertical stereophonic perception: Perceptual Band Allocation (PBA) and phantom image elevation effect. The PBA renders vertical image spread in front of listener by allocating each sub-band signal to either lower or upper frontal loudspeaker layer depending on the unique vertical position of the band. The phantom image elevation effect depends on loudspeaker base angle, sound source type and frequency. Coherent 500Hz and 8kHz bands presented from a loudspeaker pair with the base angle between 180° and 240° give rise to ‘above’ localisation while 1kHz band ‘back’ localisation. The overall result is the enhancement of immersiveness perceived across the upper-hemisphere.