Psychoacoustic Considerations in Surround Sound with Height

This paper presents recent research findings in the psychoacoustics of 3D multichannel sound recording and
rendering. The addition of height channels in new reproduction formats such as Auro-3D, Dolby Atmos and 22.2,
etc. enhances the perceived spatial impression in reproduction. To achieve optimal acoustic recording and signal
processing for such formats, it is first important to understand the fundamental principles of how we perceive sounds
reproduced from vertically oriented stereophonic loudspeakers. Recent studies by the authors in this field provide
insights into how such principles can be applied for practical 3D recording and upmixing. Topics that are discussed
in this paper include the interchannel level and time difference relationships in terms of vertically induced
interchannel crosstalk, the effectiveness of the precedence effect in the vertical plane, the aspect of tonal coloration
resulting from vertical stereophonic reproduction, the effect of vertical microphone spacing on envelopment, the
effect of interchannel decorrelation, and the use of spectral cues for extending vertical image spread.