Sonic City is a wearable system enabling the use of the urban environment as an interface for real-time electronic music making, when walking through and interacting with a city. The device senses everyday interactions and surrounding contexts, and maps this information in real time to the sound processing of urban sounds. We conducted a short-term study with various participants using our prototype in everyday settings. This paper describes the course of the study and preliminary results in terms of how the participants used and experienced the system. These results showed that the city was perceived as the main performer but that the user improvised different tactics and ad hoc interventions to actively influence and participate in how the music was created.