Magnus Öström was the son of an artist couple, and was influenced by the musical tastes of his older brother like Jimi Hendrix, Deep Purple, The Allman Brothers and Lynyrd Skynyrd. At the age of eight years he built his first drum set and soon played music with a friend, Esbjörn Svensson. Since 1981, he attended the musical grammar school in Västerås and played with Svensson trio. Between 1983 and 1985 he studied at the adult education center in Sjövik before he continued his studies at the Music Academy Stockholm. During this time he played with various bands of the Stockholm scene; between 1987 and 1992 he was a member of the band of singer Monica Borrfors. Since 1989, he was back with Svensson, initially in the group Stock Street B , then again in a trio with the bassist Dan Berglund with an album released in 1993. e.s.t. released twelve albums toured internationally with great success. They played until the accidental death of Svensson.