Music may arouse intense emotions in listeners, but little is known about the circumstances that contribute to such reactions. Here we report a listening experiment that investigated the roles of selected musical, situational, and individual factors in emotional reactions to music. In a 2 x 2 factorial design, we manipulated music choice (self-chosen vs. randomly sampled) and social context (alone vs. with a close friend or partner). Fifty university students (20–43 years old) rated their emotional responses to the music in terms of overall emotion intensity and 15 emotions. We also measured personality traits (NEO-PI-R) and psychophysiological responses (skin conductance, heart rate). Consistent with predictions based on previous field studies, listeners reported more intense emotions (1) to self-chosen music than to randomly selected music and (2) when listening with a close friend or partner than when listening alone. Moreover, listeners scoring high on the trait Openness to experience experienced more intense emotions than listeners scoring low. All three factors correlated positively with the experience of positive emotions such as happiness and pleasure.