The philosophies of the Enlightenment naturally affected artists, the arts, and their influence on the popular culture. The influence of the Enlightenment on classical music may be seen as a notable decline of religious compositions accompanied by a sharp rise in secular music written specifically for middle-class audiences rather than the nobility. This trend was promoted by philosophers who believed that art and music should be for everybody, not just a chosen few.
The differences in the two eras cover every aspect of music; its form, style, the way it reached the public, as well as the status of the composers. New concepts governed the grammar and syntax of music, new genres came into being, and commercial practices increasingly determined a composer's reputation and by the end of the century, the public's view of the composer had changed substantially.
It was during the classical period that the modern orchestra was founded. The full orchestra consisted of flutes, oboes, clarinets, bassoons, horns and trumpets, trombones; timpani and strings divided into first and second violins, violas, cellos and double-basses. In practice, Haydn and Mozart employed this fully orchestra very rarely, almost exclusively in opera and large-scale choral works and never in symphonies, where trombones were not used until Beethoven's time. .
Romantic composers often used books, poems, or plays as in inspiration for their music and incorporated the written word into musical pieces. The leading author of the Romantic Movement was Johann Wolfgang Von Goethe, whose books stress human passions, imagination, and freedom. This was a departure from the classical style that embraced golic, intellect, reason, balance and form. .
Classic and romantic relates to the two basic instincts of human nature.
The numerical size of orchestras in courts, churches, concert halls and theatres varied as much as their internal composition, and for any traveling musician orchestral resources were largely unpredictable.