He has been involved in numerous projects during the years, composing much of the music in addition to playing keyboards on the albums New Born Day (1973), Ranshart (1974) and Let Your Light Shine (1976) within the band Ruphus.

He has a long musical career behind him, and have cooperated with a series of famous musicians such as Roger Daltrey, Alan White, Jamie Moses, Natasha Beddingfield, Phil Collins, Mark Hudson and Simon Kirke.

[2] Graf also toured with renowned guitarist Frank Gambale, after being contacted by him during the 1994 Graffiti concert at Musicians Institute in Los Angeles.

Graf has also toured with Paul Jackson and Mike Clark (bassist and drummer of Herbie Hancock's Headhunters known from legendary recordings as "Thrust").

Rather than exhaust the audience with non-stop flash, he builds his solos carefully, keeping the listener interested from beginning to end.

[1] The Coast Radio, Las Vegas when reviewing Graf states: "Haakon's talent is never ending, he has great passion for his music.