The Classical period in music spans from 1750 to 1827, dominated by Haydn, Mozart, and Beethoven. It coincides with Neo-Classicism in other arts and the Enlightenment era of promoting equality through education. Music of this period features clear, elegant melodies in symmetrical phrases accompanied by gradual dynamics and regular rhythm. The piano replaces the harpsichord as a prominent instrument while the orchestra and vocal genres like opera and oratorio continue developing. Haydn, Mozart, and Beethoven make significant contributions through their symphonies, sonatas, string quartets and other instrumental and vocal works.