A Norwegian singer and bassist, born with the name Simen Hestnæs. Made his grand entry to the Norwegian metal scene when he guested on Arcturus' second LP La Masquerade Infernale in 1997. He is credited with lyrics and the dazzling, semi-operatic lead vocals on
The Chaos Path and with backing vocals on a few other songs.
He soon joined the all-star lineup of Borknagar as a vocalist, replacing Garm who was busy with his other projects (Ulver and the aforementioned Arcturus). Vortex was a member of the band for three years and contributed on two albums: The Archaic Course (1998) and Quintessence (2000). Meanwhile, he had kept himself busy by joining one of Norway's most popular black metal acts, Dimmu Borgir, filling the bassist vacancy left behind by Nagash of later The Kovenant fame. And as Dimmu Borgir began to take up more and more of his time, he eventually departed from Borknagar in 2000 to concentrate on his new main band.
Truly an accomplished singer, I.C.S. Vortex has a unique and well-trained vocal style rarely found in the black metal scene. He is capable of the mandatory guttural metal growl, but where his voice and skills really shine are the clean vocals, as shown on many Borknagar songs as well as the Arcturus collaboration. His vocal range is tremendous and his trained falsetto allows him to execute difficult melodic passages in extremely high registers.