This paper introduces a new music listening system that can alter various elements of existing music. More specifically, we propose a new role for the listener as an active agent, meaning one who can alter certain musical elements while listening, especially timbre. These changes can be made according to the user’s needs, goals, and purposes. Within the system, the music emotion controller allows listeners to control musical elements via their mobile phones. We conducted experiments to develop a new arousal-valence model of timbre, which is applied in conjunction with other musical elements to provide the listener with an adaptable interface when they listen to songs with selected emotions. We extended the

choices available to listeners by diverging from traditional listening methods.