Rachmaninoff’s piano music is mostly difficult to play. He wrote many short pieces called preludes and some studies which are some of the hardest piano music written since Liszt. As well as the "Rhapsody on a Theme of Paganini" he wrote four piano concertos. The Second and Third are very popular today, as is his "Second Symphony". The second concerto reaches the lowest C on the piano, making it one of the lowest pieces of music (this is lower than a bass, which goes down to D).