Voice production effects due to extreme reverberation times in real rooms

Abstract

Public school teachers have a heightened risk of voice problems. There are many potential causes of this increased vocal risk, including poor room acoustics (e.g., excessively high or low reverberation times). With increased understanding, rooms could be better designed to maintain communication transfer (intelligibility), while mitigating unhealthy vocal effort and, by extension, voice problems. The present study quantified the influence of a wide range of reverberation times (RT20) on vocal production parameters. Thirty-two participants were recorded completing a battery of speech tasks in eight widely ranging conditions within a reverberation chamber. Changes in RT20 had highly correlated effects on several vocal parameters, including smoothed cepstral peak prominence, acoustic vocal quality index (AVQI), and pitch strength. As RT20 increased, vocal parameters tended toward values commonly associated with dysphonic phonation. Additionally, results were gender dependent, with females tending to produce voice with higher vocal effort than males. These findings begin to objectify the effects of room acoustics on vocal accommodations and provide grounds for developing future talker-oriented room acoustical standards.