Robert Stack is a good choice for the top 10. Morgan Freeman has to be in there for Shawshank alone. If you want to extend to other media, Wayne June, the guy who did the narration for the Darkest Dungeon video game, is a must.
I would have to include Liev Schrieber for his work narrating HBO's "Hard Knocks." He does an incredible job of really bringing that old NFL Films-style voice to this show.