Konzerthausorchester Berlin  The Konzerthausorchester Berlin is a German symphony orchestra based in Berlin. The orchestra is resident at the Konzerthaus Berlin, designed by the architect Karl Friedrich Schinkel. The building was destroyed during World War II, and was rebuilt from 1979 to 1984. The orchestra was founded in 1952 as the "Berliner Sinfonie-Orchester" (Berlin Symphony Orchestra) in what was then East Berlin, as a rival ensemble to the Berlin Philharmonic Orchestra based in West Berlin. The first chief conductor was Hermann Hildebrandt. In 1974, the Berlin Sinfonietta was founded to serve as the sister chamber orchestra of the "Berliner Sinfonie-Orchester". After German reunification in 1989, the orchestra was threatened with dissolution, but subscriber action maintained the ensemble. The orchestra acquired its current name in 2006. (This orchestra is separate from the West-Berlin based Berliner Symphoniker, founded in 1967.) The "Konzerthausorchester Berlin" currently has, as its sister chamber orchestra, the "Konzerthaus Kammerorchester". Kurt Sanderling was the longest-serving chief conductor of the orchestra, from 1960 to 1977. Subsequent chief conductors have been Günther Herbig, Claus Peter Flor, Michael Schønwandt (1992–1998), Eliahu Inbal (2001–2006), and Lothar Zagrosek. In February 2011, the orchestra announced the appointment of Iván Fischer as its eighth principal conductor, effective with the 2012-2013 season, with an initial contract of 3 years. In October 2016, the orchestra announced that Fischer is to stand down as its principal conductor after the 2017-2018 season. In November 2017, the orchestra announced the appointment of Christoph Eschenbach as its next chief conductor, effective with the 2019-2020 season, with an initial contract of 3 years. Principal guest conductors of the orchestra have included Dmitri Kitayenko, the current holder of the post. With the 2017-2018 season, Juraj Valčuha became principal guest conductor of the orchestra, following his initial guest-conducting appearance with the orchestra in the 2014-2015 season, and his subsequent return guest-conducting engagement 2 years later.