/dev/dsp is the audio device in Linux. It generally is associated with oss or open sound system drivers. There is also alsa which can provide /dev/dsp. It has major number 3 and minor number 2. It is a character device, and oss commercial version give the option of the virtual mixer which creates /dev/dsp0, /dev/dsp1, etc. This allows multiple programs to access the audio device. The software mixes audio into one stream.