Development and testing of a portable vocal accumulator.

This research note describes the design and testing of a device for unobtrusive, long-term ambulatory monitoring of voice use, named the Portable Vocal Accumulator (PVA). The PVA contains a digital signal processor for analyzing input from a neck-placed miniature accelerometer. During its development, accelerometer recordings were obtained from 99 participants with normal or dysphonic voices. The recordings were used to (a) test the specifications and capabilities of the PVA for monitoring normal and dysphonic voices and (b) explore potentially useful displays for the large quantity of data generated by long-term monitoring. The current prototype PVA is pocket-sized (12 x 8.5 x 2 cm), lightweight (200 g), and capable of sampling 11 hr of voice-use data, including estimates of fundamental frequency, sound pressure level, and phonation duration.