Slettevoll was born in
Volda and is a graduate of the jazz program at
Trondheim Musikkonservatorium (2001–05).[3] He was first recognized as member of the band
The Core together with fellow students in Trondheim, Kjetil Møster, Steinar Raknes and Espen Aalberg. Later he worked with musicians like Petter Wettre and Heidi Skjerve.
Grand General is the latest project including Slettevoll. Having played a few gigs as
Kenneth Kapstad Group this lineup released their debut album Grand General in 2013. Violinist Ola Kvernberg, who was awarded
Spellemannprisen for his album Liarbird, was in the forefront. One can not help comparing the music on this album with the
Mahavishnu Orchestra, with a delicate interplay between the soloists and an impressive rhythm section.[2]