In his early career, Estonian composer Erkki-Sven Tüür straddled the line between conservatory-based classical music studies and pop music. Tüür studied flute, music composition, and percussion instruments while attending Tallinn Conservatory, and from 1979 he led a rock group called In Spe, which incorporated elements of Renaissance and Baroque music. Along the way, Tüür also composed music for theatrical productions and took some electronic music courses in Darmstadt. In Spe disbanded in 1983 (although it reunited in 2009 for a final concert), and Tüür earned his diploma from Tallinn in 1984. Tüür composed music for chamber ensembles throughout the 1980s and only accepted a post at the Tallinn Conservatory in 1989. Starting in 1984, Tüür undertook a series of works entitled Architectonics, ultimately running to seven pieces, that are scored for a variety of chamber combinations and were commissioned by ensembles ranging from Estonia to Los Angeles. Tüür's String Quartet (1985) begins to demonstrate some elements of his mature approach, which is informed by the rhythmic propulsiveness of minimalism, yet incorporates harmonic gestures and effects from the avant-garde and other styles not readily associated with minimalist music. With Tüür's Requiem (1994) his reputation was made, and soon he became one of the most frequently performed composers in Estonia. Tüür was able to quit teaching and go into music composition on a full-time basis. From this time, increasingly more diatonic elements begin to appear in the works of Tüür, and in addition to this there is a shift of focus from chamber music to orchestral and large choral works. In 2002 he developed a method of composition he called "vectoral writing," a technique that yields harmonic variety through voice leading and the use of a numerical code. Tüür has written a Mass, an oratorio Ante Finum Saeculi, symphonies, concerti, several pieces for orchestra, and a wide variety of chamber works. Tüür's music has been performed by Isabelle van Keulen, Anu Tali, Tönu Kaljuste, David Geringas, Evelyn Glennie, Paavo Järvi, and the California EAR Unit; and has been recorded to a significant extent, particularly on the ECM label. The recording of his Piano Concerto and Symphony No. 7 was nominated for Gramophone magazine's 2014 awards. Tüür is a co-director of the International Contemporary Music Festival NYYD held in Tallinn, and has been honored several times by organizations for his contributions to Estonian culture.