Mozart called it the”king of instruments.” It’s the pipe organ, and it isn’t just for churches any more. This month, Nashville joins a growing roll of cities like L.A, Philadelphia, and Jacksonville that have recently added pipe organs to their symphony halls. But these intricate instruments don’t ship ready-to-play. Some assembly may be required. WPLN’s Kim Green listens in on the final step of installing the pipe organ – adjusting and tuning its mighty sound.