Steef van Oosterhout graduated as a soloist from the Sweelinck Conservatory in Amsterdam in 1987. He worked as a chamber musician in the Netherlands and performed with most of the country’s symphony orchestras, including the Royal Concertgebouw Orchestra in Amsterdam, before joining the Iceland Symphony Orchestra in 1991.He is a member of the CAPUT Ensemble and the percussion ensemble Benda and has taken part in a wide range of chamber music projects, including performances at the Reykjavík Midsummer Music festival.Together with his wife, violist Herdís Anna Jónsdóttir, Steef founded Dúó Stemma in 2002. The duo has given numerous concerts for children and adults in Iceland and abroad. In 2008, Dúó Stemma received an award from IBBY Iceland in recognition of their contribution to children’s culture in Iceland.In November 2019, they gave a family concert at the Konzerthaus Berlin.