Wearing face masks (alongside physical distancing) provides some protection against infection from COVID-19. Face masks can also change how we communicate and subsequently affect speech signal quality. Here we investigated how three face mask types (N95, surgical and cloth) affect acoustic analysis of speech and perceived intelligibility in healthy subjects. We compared speech produced with and without the different masks on acoustic measures of timing, frequency, perturbation and power spectral density. Speech clarity was also examined using a standardized intelligibility tool by blinded raters. Mask type impacted the power distribution in frequencies above 3kHz for both the N95 and surgical masks. Measures of timing and spectral tilt also differed across mask conditions. Cepstral and harmonics to noise ratios remained flat across mask type. No differences were observed across conditions for word or sentence intelligibility measures. Our data show that face masks change the speech signal, but some specific acoustic features remain largely unaffected (e.g., measures of voice quality) irrespective of mask type. Outcomes have bearing on how future speech studies are run when personal protective equipment is worn.

中文翻译：

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口罩对声学分析和语音感知的影响：对大流行性疾病协议的影响

戴上口罩（与身体保持距离）可提供一些保护，防止感染COVID-19。口罩也可以改变我们的沟通方式，进而影响语音信号质量。在这里，我们研究了三种面罩类型（N95，外科手术和衣服）如何影响健康受试者的语音声学分析和可感知的清晰度。我们在定时，频率，扰动和功率谱密度的声学度量上比较了有无面具时产生的语音。盲目评分者还使用标准化的清晰度工具检查了语音清晰度。N95和手术口罩的口罩类型都会影响3kHz以上频率的功率分布。定时和频谱倾斜度的度量也因掩模条件而异。倒谱和谐波噪声比在整个面罩类型中保持不变。单词或句子清晰度测试条件在所有条件下均未观察到差异。我们的数据表明，口罩会改变语音信号，但是某些特定的声学特征在很大程度上不受影响（例如，语音质量的度量），而与口罩的类型无关。结果与穿戴个人防护设备时未来语音学习的进行方式有关。