Loudness Threshold as a Function of Sound Source Location Using Circum-Aural Headphones in Noisy and Sound-Proof Acoustic Environments

We compared custom-made headphones (designed to capitalize on the directional filtering capability of the external ear) with standard consumer headphones in a loudness threshold task, and had shown that the location of the speakers was essential to auditory perception. The results revealed that the equal loudness contour profiles were significantly changed using the customized headphones. Furthermore it was discovered that an everyday noisy acoustic environment as compared to a sound-proof room does not diminish the advantage of the customized headphones in an auditory threshold task. Future investigation of the filtering process that the external ear provides could lead to more ergonomic acoustic equipment and hearing aid design.