Wireless comms nearly always focus on the EM spectrum- RF, microwave, even laser. But what about sound? Motivated by Dragos's badBIOS work, richo sat down to reimplement a subset of the original capabilities at a high level in userland. Having already produced the Groundstation framework for distributed communications, the next logical step was to produce an audio bridge, the result of which is that nodes with working sound hardware can communicate structured data when physically proxmiate, without any other shared state.