The clarinet played by Ensign Harry Kim, once a member of the Juilliard Youth Symphony, who replicated a new one aboard Voyager and performed for the crew.
Harry Kim is an accomplished clarinettist. He left his own instrument behind on Earth when he joined Voyager, and early in the journey he spends precious replicator rations on a replacement.
His playing is shown in several Voyager episodes. In The Thaw he is practising in his quarters when the story begins, to the irritation of his neighbours, and in Night, during the crew's passage through a starless void, he performs a piece of his own composition for the captain on the bridge.
Kim goes on playing in later seasons, alone and with other musicians among the crew, and the clarinet remains the instrument most associated with him, a reminder of the family and musical training he left behind.