Motion Simulation in the Environment for Auditory Research
Abstract
Virtual sound source motion has been implemented in the U.S. Army Research Laboratory's Environment for Auditory Research, which contains a 57-channel spherical loudspeaker array located in a semi-anechoic chamber. Using the low-latency PortAudio application programming interface from the Psychophysics Toolbox Version 3, we are able to dynamically update 57 channels of streaming audio in real time using MATLAB for signal processing. Both Distance-Based Amplitude Panning (DBAP) and Vector Base Amplitude Panning (VBAP) have been implemented in MATLAB for controlling source motion. Sources are defined on a given path, such as a circle, ellipse, or the "dog bone" pattern often used in aviation. Although DBAP works convincingly for virtual sources located on the sphere defined by the loudspeaker array, VBAP is needed to position sources outside the array. Source motion paths are defined parametrically with respect to time, and the playback buffer updates the panned position every 11.5 ms. Based on the source's instantaneous distance, diffuse-field or free-field amplitude attenuation is added in MATLAB, as is air absorption filtering. This virtual sound source method will be used for a variety of audio simulations and auditory experiments.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 01, 2011
- Accession Number
- ADA558387
Entities
People
- Braxton Boren
Organizations
- United States Army Research Laboratory