Previous research recognizes the importance of musical experiences on music teacher education. However, current efforts do not provide a comprehensive view of the way their students learn music before starting university. The objective of this study is to portray their musical experiences, identifying the distinctive mechanisms underlying the relationship between practices, repertoires, and training contexts for music learning. A combination of pedagogical, social and musical dimensions, inspired by sociological theories of P. Bourdieu and B. Bernstein, examine the pre-university musical experiences and the mediating role of students' sociocultural origins. Empirically, multimodal information from four Chilean universities (n = 55) was collected through the application of a survey questionnaire and semi-structured interviews, and analyzed using a set of mixed techniques, including descriptive statistics, text mining, and content analysis. Findings reveal relevant associations between practices, repertoires, and learning contexts, especially in terms of the specialized nature of musical training and the habitus and cultural dispositions of practitioners. Particularly relevant is the predominance of informal and non-formal learning contexts and their translation into specific types of learning. These challenge current perspectives and contribute a tool kit for the understanding of the relationship between power and knowledge in future professional teachers.