This last Saturday marked the 100th anniversary of Rachmaninoff’s third piano concerto. I don’t know if there were any performances anywhere to commemorate the piece, but then again, we don’t often commemorate pieces. Usually, it’s the life of the composer we celebrate. Still, I like to think about the significance of a musical work coming into existence, to fill an ethereal space where once there existed a musical void. Before November 28th, 1909, no one knew what the third concerto by Rachmaninoff sounded like, save the composer himself....