Mellodium

This article contains information from the Warcraft RPG which is considered non-canon.

A melodium can capture a performance on a musical instrument and later use the instrument to replay the performance automatically. Each type of instrument requires its own type of mellodium. The music is captured to a hard wax tablet inside the mellodium, and can be replayed at any time using a mellodium attached to the same instrument; though other mellodiums use the same tablets, music recorded on other instruments will be played as noice.