Before the Baroque era, music was rarely written specifically for instruments; very often, the music played on instruments was originally for the voice. The Baroque era lasted from 1600 to 1750. During this period instruments were improved and composers began writing pieces for specific instruments. Music became more popular among the middle class, and amateur musicians began to appear, separate from church and court. Instrumental music in the late Renaissance and early Baroque was called sonatas, concertos, and symphonies interchangeably. The order and form of their movements were often very similar. Works that used five to seven violins with continuo were often called sonatas and concertos, although they were more often called canzonas. Before Corelli's concerto Grosso, concerts often designated music that used both instruments and voices. However, during the last quarter of the 17th century, concerto denoted purely instrumental music, unless the title of the piece specified otherwise. However, in 1680, some ground rules were established. The first generation of the concerto Grosso was typically for violins. Arthur Hutchins, regarding Corelli and Vivaldi, says that “the violin was a wordless voice with a superhuman compass and range of expression, with a clearer attack and greater agility than a human voice, and free from the tension of human toil ”. This belief that violins could emulate the human voice led to a golden age for string ensembles. Concertos normally consisted of six to twenty strings, with organ, harpsichord and archlute. In 1686 Torelli wrote the first piece that did not include vocals. It was called Chamber Concerto for two violins and bass; this...... middle of sheet......: Novello Co., LTD., 1946.Dorian, Frederick. The history of music in performance. New York: W. W. Norton & Company Inc., 1942.Harman, Alec. Late Renaissance and Baroque music. Fair Lawn, New Jersey: Essential Books, 1959.Hutchings, A. J. B. The Baroque Concert. New York: W. W. Norton & Company Inc., 1965.Newman, William S. The Sonata in the Baroque Era. Raleigh, North Carolina: The University of North Carolina Press, 1966. Palisca, Claude V. Baroque Music. Englewood Cliffs, New Jersey: Prentice-Hall Inc., 1968.Peyser, Joan ed. The Orchestra: origins and transformations. New York: Charles Scribner's Sons, 1986. Ripin, Edwin M. “Pianoforte.” Grove Music Online. Oxford Music Online. Oxford University Press. Network. November 22. 2013.