Compact Speaker Array for Clinical Testing of Ear-level Devices

This project addresses the need for a compact loudspeaker array to test spatial hearing in audiometric sound booths. Spatial hearing tests, especially tests of sound localization and spatial unmasking of speech reception, are needed both for qualifying prospective equipment and for assessing fitness for duty of military personnel. Work in Phase I will address the acoustic issues that arise from having nearby loudspeakers in unknown acoustic environments. Among these issues are the minimal allowable distance between loudspeaker and listener, the need to minimize head movements, loudspeaker selection, the role of reverberation and variability in it across test sites, and the need for user-friendly calibration. Phase I will result in a prototype loudspeaker array housed in a streamlined cabinet that protrudes minimally from the walls. The size of the array can be customized, while the loudspeakers within the array can be adjustably placed for custom configurations. Subsequent Phase II work will: address hardware issues related to processors (PC and Android tablet) and amplifiers; determine the need for methods to combat reverberation variability; and assess the reliability of tests with the array system conducted across different test sites.Ten final systems will be delivered at the end of Phase II.