This paper reports results from three experiments using the Musical Ear Test (MET), a new test designed for measuring musical abilities in both musicians and non-musicians in an objective way with a relatively short duration (less than 20 min.). In the first experiment we show how the MET is capable of clearly distinguishing between a group of professional musicians and a group of non-musicians. In the second experiment we demonstrate that results from the MET are strongly correlated with measures of musical expertise obtained using an imitation test. In the third experiment we show that the MET also clearly distinguishes groups of non-musicians, amateurs and professional musicians. The test is found to have a large internal consistency (Cronbach alpha: 0.87). We further show a correlation with amount of practice within the group of professionals as well as a correlation with a forward digit span test. (Contains 3 tables and 5 figures.)