Design Process of a Head-List Mounted Microphone System for BRIR Measurements in Personal Sound Zone Research

Abstract

The purpose of this design project is to create a lightweight headset that holds 14 microphones. In multiple tests, 14 simultaneous pulses must be emitted from the microphones to train the Spatially Adaptive Neural Network (SANN), which generates the Personal Sound Zone (PSZ) with its data. Apart from the Head and Torso Simulator for testing, it needs to fit human heads of varying sizes as well. Lightweight materials were chosen, such as 3D-printed plastic and Velcro-One. The holders for the microphones were designed to be in a T-shape with 8 mm holes for each microphone and an earbud to hold them in place. The headset consists of 1 headpiece, 2 microphone holders, 3 feet of Velcro-One, an “X” clip to hold them in place, 4 threaded rods, 4 wing nuts, and 4 regular nuts. I completed the main design requirements, but many requirements still need many more iterations to be fulfilled. When evaluating the design, it proved to be comfortable for a human head, but no research can be done with it. While the headset was successfully proportioned for a human head, it could not fit the proportions of the sound dummy head. While the dimensions for human heads were available, the sound dummy’s technical drawings were impossible to find. Additionally, the supports used to hold the microphones and their holders are metallic and cause acoustical interference and reflections. In the end, my client considered the design a good prototype at its final iteration.