The primary functions of MIDI Cables include communicating event messages about musical notation, pitch, velocity, control signals for parameters, such as volume, vibrato, audio panning, cues, and clock signals (to set and synchronize tempo) between multiple devices; these complete a signal chain and produce audible sound from a sound source. For users, MIDI enables a single player to sound as though they are playing more than one instrument simultaneously. As an electronic protocol, it is notable for its widespread adoption throughout the music industry.