Effects of masker similarity on the identification and localization of vehicular sounds

Several experiments were conducted to determine the effects of masking sound similarity on the identification and localization of airborne and ground vehicle sounds. In some experiments, natural masking sounds were played in the presence of target vehicle sounds. In other experiments, spectral and temporal cues were artificially manipulated to determine their individual effects on identification and localization performance. The Environment for Auditory Research of the Army Research Laboratory was used to create ambient masking sounds. In general, masking sounds that were similar to the vehicle sounds in spectral and envelope shape were more effective than dissimilar sounds in reducing auditory perception abilities of the listener. Although the complexity of most vehicle sounds enabled the listeners to correctly identify and localize the vehicle sounds in many masking conditions. The results of these experiments will be discussed in terms of the aural abilities of human subjects to identify and localize vehicle sounds in various ambient masking conditions.