Distributed acoustic sensing underlies an increasingly important class of sensor network applications, from habitat monitoring and bio acoustic census to security applications and virtual fences. VoxNet is a complete hardware and software platform for distributed acoustic monitoring applications that focuses on three key goals:(1) rapid deployment in realistic environments;(2) a high level programming language that abstracts the user from platform and network details and compiles into a high performance distributed application; and(3) an interactive usage model based on run-time installable programs, with the ability to run the same high level program seamlessly over live or stored data. The VoxNet hardware is self-contained and weather-resistant, and supports a four-channel microphone array with automated time synchronization, localization, and network coordination. Using VoxNet, an investigator can visualize phenomena in real-time, develop and tune on-line analysis, and record raw data for off-line analysis and archival. This paper describes both the hardware and software elements of the platform, as well as the architecture required to support distributed programs running over a heterogeneous network.We characterize the performance of the platform, using both microbenchmarks that evaluate specific aspects of the platform and a real application running in the field.