Free improvisation or free music is improvised music without any rules beyond the logic or inclination of the musician(s) involved. The term can refer to both a technique (employed by any musician in any genre) and as a recognizable genre in its own right. Free improvisation, as a genre of music, developed in the U.S. and Europe in the mid to late 1960s, largely as an outgrowth of free jazz and modern classical musics. None of its primary exponents can be said to be famous amongst the general public .
Derang Duet Derang started in May 2012, with cooperation of Ahoo Maher & Ayrin Moradi. Following their interest in modern music, these two musicians, who had been playing classical music for more than 10 years, try to practice new experiences under the name of Derang. In developing every project, they have a specific concept in mind, however they don’t simply seek to convey these concepts to the audience, since every individual impressions are of great value for them. Group members had passed courses of free improvisation under the instruction of great musicians such as Burkhard Stangl, Gunter Schneider & Manon-Liu Winter at Universität für Musik und darstellende Kunst Wien. They also have taken part in workshops held by John Tilbury, a well-known pianist and improviser at AMM. The idea of formation and the first performance of Derang on stage were at the 10th anniversary of Free Improvisation at Universität für Musik und darstellende Kunst Wien, where they played a piece called »Aufruf«. The second Performance of Derang [su:r] was performed in february 2014 in Tehran at Shirin Gallery and the third performance was in Vienna echoraum.