An open air concert is a concert taking place outside a hall in the open air.
Open air concerts can range from small, acousitic gatherings taking place at a municipal park, to large multi-day music festivals, involving some of the most famous music acts in the world. Nearly any type of music can be played at one of these concerts, and they frequently feature pop, folk, classical, or jazz artists. Largely electronic music, such as techno, are seldom featured because of the difficulties of staging the event. Some open air concerts known as festivals take place over several days and feature a large number of different artists.
Open air concerts take great amounts of planning, to make sure that the stage is visible from the entire audience seating area. Frequently, the area directly in front of the stage is kept clear for dancing. In the case of punk concerts and other energetic music, this area becomes a mosh pit filled with a violently moving crowd. Generally, care is taken to keep the dancers off the stage, however at punk concerts, stagediving and other audience interaction are more common.
Open air concerts can be free for the audience, or may sell tickets for entrance. With ticketed events, these concerts are staged in planned, fenced-in areas, to avoid non-paying visitors. The fencing used is often temporary.
Rain can wreak havoc at an open air concert. The grass in front of the stage is often heavily damaged by concert-goers, and may need replanted after the event. Therefore it is common, that visitors at some ticketed open air concerts get a part of their money back, when they donate a sack of grass seed at the entrance of the open air concert.
Concerts can take place at a location not served by the public electricity grid. In these cases, the concert promoters set up emergency power generators.
Many open air concerts are very loud, and without the insulation of a building or arena to contain the noise, this also takes an amount of planning, to assure that the concert does not bother the neighbors. Often, these events are staged at a distance from residential areas. Many areas have noise regulations in place limiting the areas in which these large events can take place.
For larger events, the stage is built from scaffolding and often includes a roof to protect electrical equipment from potential rain. This scaffolding rig holds lighting and other special effects equipment. Loudspeakers are frequently mounted to the right and left of the stage in towers, with the mixing console placed before the stage.
Support functions are often placed in areas surrounding the audience. Concessions are sold from trailers and other temporary structures. If plumbing facilities are available, toilets are found in this area; in areas without plumbing, chemical portable toilets are used.