Sinopoulos was born in Athens in 1974. He studied classical guitar with B. Gratsounas and theory of western music with M. Adami, while taking lessons in Byzantine music and demotic (folk) song, initially at S. Karas’ school and then at I. Tsiamoulis’ where he sang with the school's children’s choir. In 1988 he started studying kementsé and polítiko laoúto with Ross Daly and a year later he joined his group "Lavyrinthos". In 1990 he represented Greece in a world conference of young musicians (JMF - Jeunesse Musiqual de France) in Paris.
In the last ten years Sinopoulos has collaborated with composers, musicians and singers from Greece and abroad in various genres, from demotic song to jazz, participating in countless conserts and recordings and helping re-introduce the kementsé in Greek music. He was recently honored with the Melina Mercouri national award for young artists. He is a graduate of the Department of Music Studies at the University of Athens, and under a grant from the Onassis Foundation he is completing his dissertation on "The theory and application of 'makam' in the scholarly musical tradition of Constantinople".