To date, little has been written on digital game sound as Games Studies has almost exclusively treated and discussed digital games as a visual medium. This paper explores how sound possesses the ability to create perceptions of a variety of spaces within the game world, thus constituting a significant contributing factor to player immersion. Focusing on First-Person Shooters (FPS), we argue that player(s) and soundscape(s), and the relationships between them, may be usefully construed and conceptualized as an acoustic ecology. An argument is presented that, even though its sonic palette may be smaller, the FPS acoustic ecology emulates real world ecologies as players form a vital component in its construction and maintenance. The process of building a conceptual framework for understanding and testing the function of game sound as an acoustic ecology is broadly outlined, involving the application and extension of a disparate range of media sound theories in addition to the construction of new concepts to account for the unique features of the interactive medium of FPS games.