Variability of speech spectra in offices by room types and communication methods

Abstract

The acoustic characteristics of room environments can significantly influence speech levels and spectra, an aspect often overlooked in the current method for predicting speech privacy. This paper presents an investigation into the variability of speech spectra in various office contexts, with a specific focus on the influence of room type, communication medium, and language. The study involved over 70 workers in different office room types in Quebec, Canada, who participated in measuring speech spectra within those spaces. Two communication methods, in-person and video-conferencing scenarios, were utilized with participants using either English or French languages. The real-world scenarios shed light on the significant impact of various parameters on speech characteristics within office settings. Comparing the results with standardized speech levels and spectra from ASTM and ISO standards, derived from controlled environments like anechoic chambers, the study reveals significant differences when applying the standard speech spectra to actual office environments. Based on these findings, the study proposes potential modifications to the existing standards, aiming to enhance the accuracy of speech privacy and intelligibility predictions.