Looking for a story

Im looking for a story i think it might have been on saphires but not 100% sure.

I think it started with the main character at school playing a piano recital (i think) at an open day or something. The character then gets involved with an orchestra and becomes a well known and travels alot. There is a point i think where they go to an army base to play and there is a part of the story where they stayed in a beach house. Anyone have a clue at what story it was please? ^_^