sentences:  Gunter Hampels quintet "Heartplants" and "Voices" by the Manfred Schoof quintet are two excellent examples of this independent European free jazz development.A founding member of the Globe Unity Orchestra since 1966, Niebergall collaborated with many musicians playing freely improvised music, including Peter Brötzmann, Don Cherry, Alfred Harth, Evan Parker, Alexander von Schlippenbach, Irène Schweizer, John Tchicai.During the early 1970s he played in Albert Mangelsdorff's various quartets and quintets.