Virtual Audio Cable is a software product based on WDM multimedia driver that allows a user to transfer audio streams from one application to another. Any application is able to send an audio stream to the input side of a "virtual cable" while a corresponding application can receive this stream from the output side. Since all transfers are made digitally, there is no loss in sound quality. VAC is the audio equivalent of a MIDI loopback device such as or Hubi, and can be used instead of "Stereo Mix" or "What U Hear" features of audio adapters.