Analysis of the dependencies between parameters of the voice at the context of the succession of sung vowels

The article presents the results of signal analysis of the recorded singing voice samples. For that study the recorded samples of the "a-e-i-o-u" exercise is analysed. Some significant parameters describing voice have been estimated. Among the estimated parameters are: pitch, calculated with the use of autocorrelation method, values of the first five harmonics, set of parameters containing first five formants and the value of vibrato parameter. The analysis of those parameters allowed, among others, to draw conclusions about dependencies of their values for different sung vowels. The study is a part of a broader research on singing voice signal analysis. The results may contribute to the development of the diagnostics tools for computer analysis of singer's and speaker's voices. The authors try to find an answer to the question whether the dependencies observed between the parameters may be useful to evaluate the quality of singing. This may be useful when designing a computer based singing assessment systems.