Virtual Audio Cable is a Windows multimedia driver allowing you to transfer audio (wave) streams from one application to another. It creates a pair of Wave In/Out devices for each cable. Any application can send audio stream to Out device, and any other application can receive this stream from In device. All transfers are made digitally, providing NO sound quality loss. VAC is a "wave-version" of the "MIDI loopback cable" like MultiMid or Hubi's Loopback drivers.

If more than one applications are sending audio to VAC, it will mix all streams together. If more than one applications are receiving audio from VAC, it will share the same audio data between all targets.

VAC is useful to record application's audio output in real time (for example - Generator, Reality or other software synth), or transfer a sound stream to another application processing it. You can, for example, use two or more software audio generators/synthesizers/sequencers to produce audio streams sending them to VAC Out, and record the mixed stream from VAC In using any recording software - Windows Sound Recorder, Sound Forge, WaveLab, Cool Edit, Gold Wave, Cakewalk, Cubase etc.