[Spectrographic study of voice disorders: subharmonics]. / Estudio espectrográfico de la disfonía: subarmónicos.

ABSTRACT

The presence of subharmonics in abnormal adult voices (polyps, polypoid degeneration, plicae ventricularis) was investigated. Subharmonics are low-frequency modulations located between two consecutive harmonics in the spectrum. Spectrum analysis was performed on 115 abnormal voices, of which 36 (31%) had subharmonics. Thirteen of the 36 voices with subharmonics had normal jitter and shimmer, so the rough voice was characterized acoustically not only by jitter and shimmer but by the presence of subharmonics in the spectrum. Subharmonics may correspond to a qualitative change in the behavior of the vibratory system.