Joe Negri reminds Mr. Rogers of the time Wynton Marsalis visited the music store back in episode 1563, "Celebrations (3)."
King Friday: I was just thinking. How can one person be a king, a father, a husband, an uncle, and a fine bass violinist?
Lady Aberlin: Hmm, that is profound. I guess one person can be many things.
King Friday: Lovely thought.
Lady Aberlin: Yes.
Carl McVicker was the regular bass player on the show's house band from August 1979 to August 2001.