There was a chapel in the castle grounds, but Prince Leopold, Bach’s employer, preferred not to have elaborate church music, so Bach’s duties were mainly confined to secular (non-religious) music. The prince was an enthusiastic amateur musician and encouraged Bach to write instrumental music. During this short period of 6 years, Bach composed most of his best known chamber and solo instrumental pieces. His compositions at this time included the 6 Brandenburg Concertos, the 6 suites for solo cello, the 6 partitas and sonatas for solo violin, as well as the famous set of 48, preludes and fugues entitled the Well-Tempered Clavier. Performances were held in rooms in the castle and would have been attended by a small number of dignitaries. There was a core of eight or nine professional musicians who were supplemented on occasion by musicians from the town and elsewhere. The music was clearly chamber music, rather than orchestral music in the modern sense.