Board Thread:Consensus Track/@comment-184.97.115.167-20150621211351/@comment-26662848-20150621215036

Yeah, Tolfdir should be right beside the bars. You need to get close to him, right up next to the bars, and he should initiate a conversation saying something like "what in the world was that noise?". Then he'll tell you to wear the amulet, after which you cast a spell at the resonating wall.

If the above didn't happen, something's not right. Try to reload an earlier save and make sure it doesn't bug the next time.