By the late 1750s there were flourishing centers of the new style in Italy, Vienna, Mannheim, and Paris; dozens of symphonies were composed and there were bands of players associated with musical theatres. Opera or other vocal music accompanied by orchestra was the feature of most musical events, with concertos and symphonies (arising from the overture) serving as instrumental interludes and introductions for operas and church services. Over the course of the Classical period, symphonies and concertos developed and were presented independently of vocal music.