Two-dimensional localization of a phantom sound image controlled by the level differences among four loudspeakers in a vertical plane facing a listener

The localization of a phantom sound image with four loudspeakers located in a vertical plane facing a subject was investigated. It was observed that when the lower two channels of the four loudspeakers were used, elevation of the sound image was found. It was also observed that a psychoacoustical system was used to generate and control stimuli. It was found that the size of the phantom sound image became larger when the level differences among the loudspeakers were small.