Same—different judgments concerning melodic stimuli prove to be ambiguous in their interpretation. I argue that such judgments are the result of a dual process. The subject's musical experience may determine whether he or she uses one of these processes or both. The first process may be adapted to the contour and the second to the scale of the melody. According to Dowling (1978), subjects use contour but do not use all aspects of scale in making same—different judgments. In the present experiment musically experienced subjects were required to judge the similarities between three-tone motifs that were heard in close succession. Directional contour proved to be the most important attribute, but all aspects of the scale were also utilized in making the judgments. If contour and scale are processed separately, experienced subjects use at least a dual mechanism in processing both attributes. Some further evidence shows that contour and scale are processed separately.