Within recent years, there has been a renewed focus on sound in urban environments. From sound installations in public space to sound festivals in alternative settings, we find a common interest in sound art relating to the urban environment. Artworks or interventions presented in such contexts share the characteristics of site specificity. However, this article will consider the artwork in a broader context by re-examining how sound installations relate to the urban environment. For that purpose, this article brings together ecology terms from acoustic ecology of the sound theories of the 1970s while developing them into recent definitions of ecology in urban studies. Finally, we unfold our framing of urban sound ecologies with three case analyses: a sound intervention in Berlin, a symphony for wind instruments in Copenhagen and a video walk in a former railway station in Kassel. The article concludes that the ways in which recent sound installations work with urban ecologies vary. While two of the examples blend into the urban environment, the other transfers the concert format and its mode of listening to urban space. Last, and in accordance with recent soundscape research, we point to how artists working with new information and media technologies create inventive ways of inserting sound and image into urban environments.