Meditation Maestro is an achievement/trophy you can get in Chapter 7 - 'The Attic'. During this chapter, you will need to fly through floating notes and knock them into the note cutouts above the doors. Once you do this, the door to the Symphony area will open and you can enter it. Inside you will find a drum with two seats where you can meditate. The first person to meditate will unlock this trophy/achievement. You can do this in local co-op or online co-op. You have to do this together though, or soon after each other.