Search

Smartphones allow good quality recordings; however, it cannot be claimed that the acoustic parameters obtained from them are comparable to those obtained with a professional microphone. The objective of this study is to establish whether there are significant differences when comparing the values of six acoustic parameters obtained from recordings using four smartphones and a professional microphone. The Praat programme was used to obtain the acoustic parameters: f0, Jitter, Shimmer, HNR, Alpha Ratio and L1 - L0 of the recording of a sustained vowel /a/ using iPhone SE, iPhone 6, Samsung S8, Huawei Y7 and the Behringer ECM8000 microphone. The sample was made up of 26 men and 26 women, from 18 to 26 years old without declared voice pathology. The repeated sample ANOVA test was used to compare the values. All the equipment show reproducibility between consecutive repeated measurements. The parameters f0 and Jitter were the only ones that did not show significant differences between the smartphones and the professional microphone. None of the smartphones studied can replace the professional microphone in voice recording for the evaluation of the six parameters analysed, except for f0 and Jitter.

Introduction and objectives Acoustic analysis is a tool widely used by professionals related to the study of voice that gives us information from a recording. It has been identified that in investigations carried out today that involve acoustic analysis, the recording process takes place in rooms with different levels of background noise. The objective of this study is to establish whether the acoustic parameter, Harmonic to Noise Ratio (HNR) varies in relation to the different background noise levels of the premises where the recording is made and recommend a maximum level of background noise. Methods Through the Praat programme, the average value of the acoustic parameter HNR of 43 subjects was obtained, inside the audiometric booth of the Universidad Autonoma de Chile, whose background noise level is 28.1 dB (A) and it was compared with the HNR average values obtained with higher background noise levels. Results The HNR average values decreased from 19.8 dB (A) to 14.0 dB (A) as the background noise level of the premises increased from 28.1 dB (A) to 57.8 dB (A). The t-test for dependent samples was performed, with which the HNR average values obtained were compared with the baseline background noise level (28.1 dB (A)). Significant differences were found with the baseline background noise level when the room noise level was higher than 47.7 dB (A). Conclusions The background noise of the premises where the voice recording for the acoustic analysis is performed, influences the value of the acoustic parameter HNR, which decreases as the background noise of the premises increases. It is recommended that the background noise level should not exceed 43.8 dB (A).

Resumen Introduccion y objetivos El analisis acustico es una herramienta muy utilizada por los profesionales afines al estudio de la voz que permite obtener informacion de ella a partir de una grabacion. Se ha identificado que en las investigaciones que se realizan hoy en dia que involucran analisis acustico, se realiza el proceso de grabacion en recintos con distintos niveles de ruido de fondo. El objetivo de este estudio es determinar si el parametro acustico harmonic-to-noise ratio (HNR) varia en relacion con los distintos niveles de ruido de fondo del recinto donde se realiza la grabacion y determinar un valor maximo recomendado de ruido de fondo para esa sala. Metodos A traves del programa Praat se obtuvo el valor promedio del parametro acustico HNR de 43 sujetos, en el interior de la cabina audiometrica de la Universidad Autonoma de Chile, cuyo nivel de ruido de fondo es de 28,1 dB(A), y se comparo con los valores promedio de HNR obtenidos con niveles de ruido de fondo superiores. Resultados Los valores promedios de HNR fueron disminuyendo desde 19,8 hasta 14,0 dB(A) a medida que el nivel de ruido de fondo del recinto aumentaba de 28,1 a 57,8 dB(A). Se realizo la prueba t para muestras dependientes, con la cual se compararon los valores de HNR promedio obtenidos con el nivel de ruido de fondo basal (28,1 dB[A]). Se encontraron diferencias significativas con el nivel de ruido de fondo basal cuando el nivel de ruido de fondo de la sala era superior a 47,7 dB(A). Conclusiones El ruido de fondo del recinto donde se realiza la grabacion de voz necesaria para el analisis acustico influye en el valor del parametro acustico HNR, el cual desciende a medida que el ruido de fondo del recinto aumenta. Se establece como valor maximo recomendado un nivel de ruido de fondo que no supere los 43,8 dB(A).

Acoustic analysis is a tool widely used by professionals related to the study of voice that gives us information from a recording. It has been identified that in investigations carried out today that involve acoustic analysis, the recording process takes place in rooms with different levels of background noise. The objective of this study is to establish whether the acoustic parameter harmonic-to-noise ratio (HNR) varies in relation to the different background noise levels of the premises where the recording is made and recommend a maximum level of background noise.Through the Praat programme, the average value of the acoustic parameter HNR of 43 subjects was obtained, inside the audiometric booth of the Universidad Autónoma de Chile, whose background noise level is 28.1dB(A) and it was compared with the HNR average values obtained with higher background noise levels.The HNR average values decreased from 19.8 to 14.0dB(A) as the background noise level of the premises increased from 28.1 to 57.8dB(A). The t-test for dependent samples was performed, with which the HNR average values obtained were compared with the baseline background noise level (28.1dB[A]). Significant differences were found with the baseline background noise level when the room noise level was higher than 47.7dB(A).The background noise of the premises where the voice recording for the acoustic analysis is performed, influences the value of the acoustic parameter HNR, which decreases as the background noise of the premises increases. It is recommended that the background noise level should not exceed 43.8dB(A).