There are multiple artists using the name Sef 1. Yousef Gnaoui (22 juni 1984) also known as Sef is a rapper/MC from Amsterdam, The Netherlands. He got famous with the numbers: ''Stuk'' with The Partysquad, Dio, Sjaak and the the number ''Me Nikes'' with The Opposites. He is also a member of the group Flinke Namen. 2. You heard The Voice on The Reelists critically acclaimed hit Freak Mode and So Solid smashes So Grimy and Broken Silence; now meet its owner.