Listening to music has been studied as a method for combating the rapidly increasing stress levels of adolescents. Previous studies yielded inconsistent results and neglected specific factors including the time relative to the stressor and the duration of time in which participants listened to music. We conducted a survey and lab experiment to investigate the impact of these factors on the stress-reducing effect of music. The survey contained questions regarding music preference, stress, and use of music for stress reduction. In the lab experiment, the math task of the Trier Social Stress Test (TSST) was used to simulate stress in participants. Three experimental groups listened to music for either five minutes before the stressor, five minutes after the stressor, or ten minutes after the stressor; with the control group not listening to any music. Heart rate variability was continuously monitored with a wearable device, Empatica, and used to derive stress levels. The survey received 251 responses and 42 students participated the lab experiment. The results showed that listening to music before the stressor resulted in significantly lower stress levels than listening to music after the stressor (p < 0.01). This finding, contrary to our survey results, revealed that the “preventive” effect of listening to music prior to the stressor was more effective than the “remedial” effect that followed after the stressor. .