Influence of multiple moving noise distractors on spatial release from masking

Abstract

Previous studies on speech in noise are often limited to studying stationary sound sources in the virtual acoustic scene. Moving toward a more realistic acoustic environment, this study aims at expanding the knowledge of spatial release from masking (SRM) involving moving noises. Current mathematical models describe contributions of distractor asymmetry (on the same or different sides) and angular separation with the target in predicting SRM (e.g., Bronkhorst, 2000). In a previous study, we quantified SRM from single distractor traveling on a 90° trajectory. In this study, we add a second distractor to investigate how speech understanding is affected by distractors in movement in various trajectory angles, where only binaural cues are available. A speech-in-noise test with normal-hearing adults is performed using virtual binaural reproduction. Listeners are asked to identify spoken words by target in front (0° azimuth) under the presence of babble-noise distractors. Speech reception thresholds at 50% intelligibility are measured in 14 test conditions from 2 distractor spatial configurations (symmetrical vs. asymmetrical) X 7 trajectories (stationary at 0° and 90° and moving 15°, 30°, 45°, 60°, and 90°). Results will be presented to understand the role of binaural cues in speech understanding under the presence of moving noises.