ACOUSTIC CHARACTERISTICS OF ROUGH VOICE - SUBHARMONICS

This study investigates the relationship between rough voice and the p resence of subharmonics, which correspond to smaller yet distinct peak s located between two consecutive harmonic peaks in the power spectrum . Spectrum analysis was undertaken in 389 pathologic voices, of which 20 had subharmonics. Although all 20 voices had roughness perceptually , 8 had normal jitter and/or shimmer. The degree of roughness had a si gnificant inverse relationship with the frequency of subharmonics. By digital signal processing, sound samples with various types of subharm onics were synthesized and perceptually analyzed. Power and frequency of subharmonics in the synthesized sound also had significant relation ships with the degree of roughness. Rough voice is acoustically charac terized not only by jitter and shimmer but also by the presence of sub harmonics in the power spectrum. Subharmonics are important acoustic p roperties for objective evaluation of rough voices.