Indoor drumline

An indoor percussion ensemble or indoor drumline consists of the marching percussion (or battery) and front ensemble (pit or frontline) sections of a marching band or drum corps. The only exceptions are in concert divisions (e.g. Percussion Scholastic Concert Open) where the marching line is absent and the ensemble consists entirely of a pit. Indoor percussion marries elements of music performance, marching, and theater; thus, the activity is often referred to as percussion theater. Although most indoor percussion ensembles are affiliated with high schools, there are also many independent groups that draw participants from a large area. Independent groups typically start rehearsing in October, while high school groups typically start after their fall marching band season ends. Because of this, the activity is often called winter percussion or winterline.

Indoor percussion (drumline) began in 1969 at the Dassel-Cokato High School in Cokato, Minnesota, United States, pioneered by the school's band instructor Steve Johnson. Their show At the Dawn of War attracted many national as well as international musicians, specifically percussion experts. The athletic arts were looking for a new intriguing sport that could challenge and excite skilled musicians, so they started creating their own styles all over the world. Since then, marching percussion has advanced and moved into auditoriums and gymnasiums as percussion ensembles looked for ways to maintain their skills during the winter months when performing outdoors on football fields was not practical. Following in the footsteps of indoor guard ensembles, indoor percussion ensembles arrange music and motion appropriate for a more intimate setting. The activity is enjoyed throughout the United States and Japan, as Winter Guard International (WGI) provides many regional and national opportunities to compete. Percussion ensembles first appeared in WGI shows in 1993, and the theatrics, sets, and music selection has advanced throughout the activity's history. There are many organizations unaffiliated with WGI that hold smaller regional shows.

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