Factors on Perception of Simultaneous Sound Sources

The ability to perceive the direction of a sound source depends on many factors. The structures of a sound signal both in the time and the frequency domain and spatial environment are the most important factors. Also, we are able to learn how to localize better. A large experimental listening test was carried out in the Laboratory of Acoustics and Audio Signal Processing of the Helsinki University of Technology. There were 25 persons in the test and some of them were professional listeners in the Finnish Navy. The material in the listening test consisted of an authentic recording from hydrophones, sinusoidal signals, and speech. The sounds were listened to by headphones and by loudspeakers. The test signals were prepared for an 8-channel loudspeaker system and the same soundscape was auralized to the headphones. Also, adding reverberation to the auralized signals to improve spatial quality was studied