This study explores the self-reported perception of moods, emotions, and engagement of Brazilian undergraduate students enrolled in a music ensemble course. A mixed method approach was used through a convergent design. Sixteen Brazilian undergraduate students enrolled in a music ensemble course participated in this research. The Present Mood States List (PMSL) was used as a quantitative data collection instrument before and after 15 encounters (14 classes and a final concert). Analysis of quantitative data showed that 15 differences in the mood state values were statistically significant when considering all encounters and 22 differences were statistically significant in specific encounters. The qualitative data collection procedures were (1) the application of a questionnaire on emotions and musical engagement after each encounter and (2) a semi-structured group interview carried out after the fourteenth class. The qualitative data were grouped into four categories: didactics, music repertoire, moods, and data collection. According to the results, participants presented mostly positive mood states and emotions both before and after the encounters. In general, the students’ mood states and emotions seemed to influence their musical engagement, and, at the same time, their sense of musical engagement seemed to influence the presence of positive experiences.