Acoustic analysis of normal voice patterns in North Indian population

Acoustic analysis of voice provides objective values which can be used for treatment follow-up, comparison, and analysis. There are a variety of programs available for this purpose, but none of these provide a normative value. The reason being that the acoustic parameters vary with age, gender, and ethnicity. The study was done to create standardized values of acoustic parameters in north Indian Hindi speakers for clinical use.

To evaluate the characteristics of voice of the north Indian Hindi speakers across the adult population based on acoustic measures of fundamental frequency (F0), jitter, shimmer, and harmonic-to-noise ratio and to observe the gender differences in these measures.

A total of 62 (39 men and 23 women) voice samples from healthy normal voiced adults aged 18-40 years were included.

Mean fundamental frequency in males and females in the age group 18-25 is 156 and 262, respectively. Similarly mean fundamental frequency in males and females in the age group 26-40 is 141 and 253, respectively. Shimmer in the women (18-25) group and jitter in the men (26-40) group is not normally distributed. Rest all parameters were normally distributed across all groups. Fundamental frequency showed statistically significant gender differences in both the age groups. Jitter and shimmer variables were statistically significant when compared between the two genders in the age group 26-40. Harmonic-to-noise ratio showed a statistically significant difference in the age group 18-25 among both genders. There exists statistically significant negative correlation between smoothed cepstral peak prominence and fundamental frequency, Pearson's r -0.479 (P-value <0.001).

All acoustic parameters except intensity show a significant gender difference; however, the participants across each gender revealed no difference in acoustic parameters when segregated into age groups.