Answer:

bandleader

AnswerCrossword Clue
BANDLEADERFirst letter of our mystery guest
BANDLEADERBaton waver
BANDLEADERGlenn or Mitch Miller
BANDLEADERSgt. Pepper, e.g.
BANDLEADERMusical conductor ... and, literally, what the start of each answer to a starred clue is
BANDLEADERRicky Ricardo, e.g.
BANDLEADERBenny Goodman.
BANDLEADERTommy Dorsey.
BANDLEADERArm or rubber?
BANDLEADERCount Basie, e.g.
BANDLEADERCount Basie, notably
BANDLEADERRicky Ricardo was one
BANDLEADEROne who must face the music?
BANDLEADERPlayer manager