Derrick started drumming in the 1960s, at the age of six, banging furiously on the kitchen floor with two of his mum's coat hangers, to a beat on the radio. Even at this early age Derrick knew that drumming was the one thing he really wanted to do.
Born in Reykjavik, Iceland. As a child Gulli started banging on pots and pans on the kitchen floor of the family home in Reykjavik. Played guitar for two years and sang in a school band until the original drummer got sick and was forced to leave his chair. Practiced drums in the loft of the Briem family residence, while playing in high school bands and musicals, where he met Johann Asmundsson a co-founding member of Mezzoforte (1977). The pair soon met Eythor Gunnarsson and Fridrik Karlsson in a Reykjavik music store, where Fridrik sold guitars. Recorded and toured with the band internationally from 1982. Their first big worldwide success with the group was in 1983 with the U.K. dance funk hit "Garden Party" and the Surprise, Surprise album. Mezzoforte has been nominated five times as the drummer of the year in Iceland.