Loud speech in realistic environmental noise: phonetogram data, perceptual voice quality, subjective ratings, and gender differences in healthy speakers.

A new method for cancelling background noise from running speech was used to study voice production during realistic environmental noise exposure. Normal subjects, 12 women and 11 men, read a text in five conditions: quiet, soft continuous noise (75 dBA to 70 dBA), day-care babble (74 dBA), disco (87 dBA), and loud continuous noise (78 dBA to 85 dBA). The noise was presented over loudspeakers and then removed from the recordings in an off-line processing operation. The voice signals were analyzed acoustically with an automatic phonetograph and perceptually by four expert listeners. Subjective data were collected after each vocal loading task. The perceptual parameters press, instability, and roughness increased significantly as an effect of speaking loudly over noise, whereas vocal fry decreased. Having to make oneself heard over noise resulted in higher SPL and F0, as expected, and in higher phonation time. The total reading time was slightly longer in continuous noise than in intermittent noise. The women had 4 dB lower voice SPL overall and increased their phonation time more in noise than did the men. Subjectively, women reported less success making themselves heard and higher effort. The results support the contention that female voices are more vulnerable to vocal loading in background noise.