Reproducing Virtually Elevated Sound via a Conventional Home-Theater Audio System

Abstract

The success of three-dimensional (3-D) movies has driven an increase in the 3D-TV market for consumers. As such, integrating audio content with 3-D video has now become an important factor in the delivery of true 3-D perception to viewers. As a result various institutions have proposed new audio-production formats to deliver an enhanced auditory impression for 3-D media. One key aspect of those formats is to utilize height-channel loudspeakers that are installed high above listeners. However, consumers at home may find it difficult to install loudspeakers on a wall or ceiling. This paper proposes a signal-processing method that creates virtually elevated auditory imagery via a conventional 5-channel home-theater system. The proposed system has been implemented using a crosstalk-cancellation method optimized for three of the five channels in a home-theater system: center, left-surround, and right-surround. Subsequently, we evaluated the perceived positions of elevated sound sources in two conditions: one reproduced from a real loudspeaker and another from the virtual loudspeaker. The results showed that (1) sound sources that were reproduced by loudspeakers arrayed at ear level were heard to be elevated well above the listener's ear level, and (2) perceived elevation angles increased monotonically with the target elevation angles for virtual sources, although the virtually elevated sound sources did not quite reach such extreme elevations as did the physically elevated ones.