Mobile Communication Devices, Ambient Noise, and Acoustic Voice Measures.
OBJECTIVE
The ability to move with mobile communication devices (MCDs; ie, smartphones and tablet computers) may induce differences in microphone-to-mouth positioning and use in noise-packed environments, and thus influence reliability of acoustic voice measurements. This study investigated differences in various acoustic voice measures between six recording equipments in backgrounds with low and increasing noise levels.


METHODS
One chain of continuous speech and sustained vowel from 50 subjects with voice disorders (all separated by silence intervals) was radiated and re-recorded in an anechoic chamber with five MCDs and one high-quality recording system. These recordings were acquired in one condition without ambient noise and in four conditions with increased ambient noise. A total of 10 acoustic voice markers were obtained in the program Praat. Differences between MCDs and noise condition were assessed with Friedman repeated-measures test and posthoc Wilcoxon signed-rank tests, both for related samples, after Bonferroni correction.


RESULTS
(1) Except median fundamental frequency and seven nonsignificant differences, MCD samples have significantly higher acoustic markers than clinical reference samples in minimal environmental noise. (2) Except median fundamental frequency, jitter local, and jitter rap, all acoustic measures on samples recorded with the reference system experienced significant influence from room noise levels.


CONCLUSIONS
Fundamental frequency is resistant to recording system, environmental noise, and their combination. All other measures, however, were impacted by both recording system and noise condition, and especially by their combination, often already in the reference/baseline condition without added ambient noise. Caution is therefore warranted regarding implementation of MCDs as clinical recording tools, particularly when applied for treatment outcomes assessments.
Department of Otorhinolaryngology and Head and Neck Surgery, European Institute of ORL, Sint-Augustinus General Hospital, Antwerp, Belgium; Department of Speech-Language Pathology and Audiology, University College Ghent, Ghent, Belgium; Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium. Electronic address: youri.maryn@gza.be.
Youri
Y
Maryn
Center of Paramedical Studies, Utrecht University College, Utrecht, The Netherlands.
Femke
F
Ysenbaert
Department of Otorhinolaryngology and Head and Neck Surgery, European Institute of ORL, Sint-Augustinus General Hospital, Antwerp, Belgium.
Andrzej
A
Zarowski
Department of Otorhinolaryngology and Head and Neck Surgery, European Institute of ORL, Sint-Augustinus General Hospital, Antwerp, Belgium.
Robby
R
Vanspauwen
D000162:Acoustics / Q000295:instrumentation*; D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D004777:Environment; D004784:Environmental Monitoring / Q000295:instrumentation*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009622:Noise / Q000009:adverse effects*; D015203:Reproducibility of Results; D012815:Signal Processing, Computer-Assisted; D059629:Signal-To-Noise Ratio; D000068997:Smartphone; D013018:Sound Spectrography; D013061:Speech Acoustics; D013068:Speech Production Measurement / Q000295:instrumentation*; D013997:Time Factors; D014833:Voice Quality; D055815:Young Adult
Acoustic analysis; Ambient noise; Mobile recording systems; Voice