Measuring the distortion of speech by a facemask

Most prior research focuses on the reduced amplitude of speech caused by facemasks. This paper argues that the interaction between the acoustic properties of a facemask and the acoustic properties of the vocal tract contributes to speech distortion by changing the formants of the voice. Speech distortion of a number of masks was tested by measuring the increase in damping of the first formant. Results suggest that masks dampen the first formant and that increasing the distance between the mask wall and mouth can reduce this distortion. These findings contribute to the research studying the impact of masks on speech.