Department of Otolaryngology-Head and Neck Surgery, Western University, London, Ontario, Canada.
School of Communication Sciences and Disorders, Western University, London, Ontario, Canada.
J Speech Lang Hear Res. 2020 Dec 14;63(12):3991-3999. doi: 10.1044/2020_JSLHR-20-00212. Epub 2020 Nov 13.
Objectives This study aimed to evaluate the fidelity and accuracy of a smartphone microphone and recording environment on acoustic measurements of voice. Method A prospective cohort proof-of-concept study. Two sets of prerecorded samples (a) sustained vowels (/a/) and (b) Rainbow Passage sentence were played for recording via the internal iPhone microphone and the Blue Yeti USB microphone in two recording environments: a sound-treated booth and quiet office setting. Recordings were presented using a calibrated mannequin speaker with a fixed signal intensity (69 dBA), at a fixed distance (15 in.). Each set of recordings (iPhone-audio booth, Blue Yeti-audio booth, iPhone-office, and Blue Yeti-office), was time-windowed to ensure the same signal was evaluated for each condition. Acoustic measures of voice including fundamental frequency (), jitter, shimmer, harmonic-to-noise ratio (HNR), and cepstral peak prominence (CPP), were generated using a widely used analysis program (Praat Version 6.0.50). The data gathered were compared using a repeated measures analysis of variance. Two separate data sets were used. The set of vowel samples included both pathologic ( = 10) and normal ( = 10), male ( = 5) and female ( = 15) speakers. The set of sentence stimuli ranged in perceived voice quality from normal to severely disordered with an equal number of male ( = 12) and female ( = 12) speakers evaluated. Results The vowel analyses indicated that the jitter, shimmer, HNR, and CPP were significantly different based on microphone choice and shimmer, HNR, and CPP were significantly different based on the recording environment. Analysis of sentences revealed a statistically significant impact of recording environment and microphone type on HNR and CPP. While statistically significant, the differences across the experimental conditions for a subset of the acoustic measures (viz., jitter and CPP) have shown differences that fell within their respective normative ranges. Conclusions Both microphone and recording setting resulted in significant differences across several acoustic measurements. However, a subset of the acoustic measures that were statistically significant across the recording conditions showed small overall differences that are unlikely to have clinical significance in interpretation. For these acoustic measures, the present data suggest that, although a sound-treated setting is ideal for voice sample collection, a smartphone microphone can capture acceptable recordings for acoustic signal analysis.
目的 本研究旨在评估智能手机麦克风和录音环境对嗓音声学测量的保真度和准确性。
方法 一项前瞻性队列概念验证研究。两组预录制样本（a）持续元音 (/a/) 和 (b) Rainbow Passage 句子通过内部 iPhone 麦克风和 Blue Yeti USB 麦克风在两种录音环境下进行录制：隔音 booth 和安静的办公室环境。录音使用校准的仿人扬声器以固定信号强度 (69 dBA)、固定距离 (15 英寸) 呈现。每组录音 (iPhone-audio booth、Blue Yeti-audio booth、iPhone-office 和 Blue Yeti-office) 都进行了时间窗处理，以确保对每种条件评估相同的信号。使用广泛使用的分析程序 (Praat Version 6.0.50) 生成嗓音的声学测量值，包括基频 (F0)、抖动、颤抖、谐波噪声比 (HNR) 和倒谱峰值突出度 (CPP)。使用重复测量方差分析比较收集的数据。使用了两个独立的数据集。元音样本集包括病理 (n = 10) 和正常 (n = 10)、男性 (n = 5) 和女性 (n = 15) 发音者。句子刺激集的感知嗓音质量从正常到严重障碍不等，评估了相等数量的男性 (n = 12) 和女性 (n = 12) 发音者。
结果 元音分析表明，抖动、颤抖、HNR 和 CPP 因麦克风选择而显著不同，而颤抖、HNR 和 CPP 因录音环境而显著不同。句子分析表明，录音环境和麦克风类型对 HNR 和 CPP 有统计学上的显著影响。虽然具有统计学意义，但在实验条件下，一部分声学测量值（即抖动和 CPP）的差异在其各自的正常范围内。
结论 麦克风和录音设置都会导致几个声学测量值出现显著差异。然而，在录音条件下具有统计学意义的声学测量值的一小部分显示出总体差异较小，在解释方面不太可能具有临床意义。对于这些声学测量值，本数据表明，尽管隔音设置是语音样本采集的理想选择，但智能手机麦克风可以捕获可接受的声学信号分析记录。
