Acoustic Analysis of Voice in Mu'adhin and Khatib

Voice is the sound produced when air from the lungs passes through the larynx and is shaped by the vocal tract (Merriam-Webster, 2026). It is an important tool for professional voice users such as Khatibs and Muʾadhins, whose occupations require prolonged and frequent vocal use. The present study aimed to examine and compare the acoustic characteristics of voice between Khatibs and Muʾadhins using parameters such as fundamental frequency (F0), jitter, shimmer and harmonics-to-noise ratio (HNR). Thirty Malayalam-speaking male participants aged 35-55 years including 15 Khatibs and 15 Muʾadhins from different districts of Kerala were participated in the study. Voice samples were recorded using sustained phonation and analysed using PRAAT. Results revealed significant differences for all acoustic parameters between the two groups (p < 0.001). Khatibs showed higher jitter and shimmer values and lower HNR values indicating greater vocal strain, whereas Muʾadhins demonstrated higher F0 and HNR values reflecting better vocal quality. The findings highlight the impact of occupational vocal demands on voice characteristics and emphasise the importance of awareness of vocal hygiene among professional religious voice users.