Abstract: To quantify the interactions between loudness and spectral centroid, the discrimination threshold and consistency of them both in single or bivariate mode are measured respectively, when they are changed in upward and downward. The results indicate that (1) the interactions between loudness and spectral centroid is asymmetry, i.e. the influence of spectral centroid to loudness is stronger than that of loudness to spectral centroid; (2) the discrimination thresholds of loudness and spectral centroid are different when the objective variable is changed upward or downward. The results presented the quantitative characteristic of interactions between loudness and spectral centroid, and offered suggestions on further research of interferences among the auditory dimensions.