Music theorist, composer, violinist, and teacher of J. G. Graun, Giuseppe Tartini's first major appointment was as chamber musician in the court of Count Kinsky in Prague (1723). In 1728 Tartini began a school for violin players in Padua. Tartini wrote violin sonatas and concerti, chamber music, symphonies, and sacred choral works. In addition, he wrote several treatises on theory, violin technique, and ornamentation. In 1714 he discovered the combination tone (sometimes referred to as "difference tone").