Live Sound Engineering

Sound engineering is the setup and operation of a sound system for events.

"Sound is the art of creating a window through sound into the force. The din is the composite of consciousnesses. It is all the people hearing the sound. Really good musicians tune the space and a sound engineer facilitates the audience's connection with the artist."

—Geoffrey Cook

Setting Up 

Sound Equipment

Professionalism With Performers

Live sound engineers are sometimes appointed by venues and must often work with many different performers. Performers tend to be an idiosyncratic bunch second only to sound engineers themselves. It is a total breach of professionalism but engineers have almost come to blows with performers over mixing disagreements and equipment damage at rock shows.

Sound Checking

A sound check must be performed before every performance opens the doors to ensure that everything sounds good. Often the acoustics of the space or variations in equipment and setups require troubleshooting and mixing adjustments.

Setting Up Foldback Monitors

Performers need speaker monitors facing them so that they hear an undelayed sound by which to stay in sync rather than the late echoes reverberating from the back of the venue.

http://en.wikipedia.org/wiki/Foldback_%28sound_engineering%29