To sing while taking melodic dictation is a strategy employed by some Ear Training students as an aid, but there is a disagreement among the literature about its efficiency. Thus, it is important to disambiguate this question examining the contributions related to vocalization. The purpose of this research is to investigate the influence singing during melodic dictation can have over this activity, and to observe if this strategy contributes in a differentiated way for subjects in different development stages. An experimental study was conducted collectively with 68 undergraduates, which were divided in groups, one that was instructed to sing during dictation taking, and another that was instructed to stay in silence. Data collected were furthermore divided in sub-groups according to participants' study time. The results show that singing hinders the dictation performance, especially in students with less musical experience, because it deconcentrates and disturbs the individuals in the same room. Although, we suggest instructors to not discourage vocalization, and to recommend students to do it outside the classroom until they develop inner singing. Our study, however, counted on a reduced number of subjects. Future research with an increased number of participants could give rise to different conclusions.