PURPOSE: To verify the efficacy of the values of the difference between the first two harmonics to distinguish adapted voices from slightly breathy (B) or tense (S), during the emission of the long vowel /é/. METHODS: Thirty women with normal and altered voices were evaluated. Each subject's vowel "é" was recorded in order to extract the intensity of the first two harmonics, using the FFT graph. The range of the second harmonic was subtracted from the range of the first, and data were treated statistically. RESULTS: The variation between the values of H1-H2 between subjects rated 0 breathiness and tension and subjects rated 1, also in both parameters, was very high, therefore the values were not statistically significant. However, when the degrees of breathiness and tension get to 2, the variation values become more compatible with descriptions in literature. CONCLUSION: The measure studied is not efficient to distinguish adapted voices from those slightly breathy and tense, during the emission of the long vowel /é/.