Steve Downes
From Halopedia, the Halo wiki
Summary
Steve Downes is the actor who voices the Master Chief in Halo 1 and Halo 2. He is also a morning DJ for 97.1 WDRV "The Drive" in Chicago, Illinois.
Images
http://img81.exs.cx/img81/3605/stevedownessmallthumb1sj.jpg