We present a psychoacoustic experiment that explores the ability of various listeners to discriminate between the virtual auditory space (VAS) stimuli generated using different binaural impulse response functions recorded in the Sydney Opera House. The binaural head-related impulse response (HRIR) functions were recorded for a group of subjects sitting in the same seat, P34, using a log sine sweep sound source located at the centre of the stage. The VAS stimuli generated using these HRIRs consist mostly of a variety of musical excerpts, speech, and white noise. Experimental results using an ABX test procedure show that out of a total of 1350 trials, 10 subjects responded correctly in 1230 of the test trials, indicating a discrimination performance greater than 90%. We also present data indicating the types of perceptual cues that aid in binaural sound discrimination process.