Conversation so far:
When did Pharrell Williams sign on to the Voice?
Pharrell Williams was a coach for the seventh season of The Voice.
What season was Pharrell Williams a coach for the voice?
Pharrell Williams was a coach for the seventh to tenth seasons of The Voice.

Question: What is he presently doing since the voice?
Self-contained rewrite: What is Pharrell Williams presently doing since the voice?