Concerto (Bach)

Johann Sebastian Bach's Violin Concertos, BWV 1041–1043, and his six Brandenburg Concertos survive in their original instrumentation. His harpsichord concertos are mostly adaptations of concertos originally written for other solo instruments.

In his early career Bach transcribed concertos by other composers for organ (BWV 592–596) and for harpsichord (BWV 972–987). His Italian Concerto, for two-manual harpsichord, was published in 1735.

The earliest documentary traces of Bach's involvement with the concerto genre include:

Bach wrote most, if not all, of his concerto transcriptions for organ (BWV 592–596) and for harpsichord (BWV 972–987) from July 1713 to July 1714. Most of these transcriptions were based on concertos by Antonio Vivaldi. Other models for the transcriptions included concertos by Alessandro Marcello, Benedetto Marcello, Georg Philipp Telemann and Prince Johann Ernst of Saxe-Weimar.

The Sonate auf Concertenart (lit. sonata in the style of a concerto) format appears for example in Bach's organ sonatas.

Apart from adaptations of movements of his earlier concertos into his cantatas, Bach also directly composed movements of his vocal works in the concerto form: for example the opening chorus of his cantata BWV 7 has been described as having the format of an Italian violin concerto movement. Another example is the opening choral movement of Bach's Magnificat, the form of which only becomes, in Spitta's words, "thoroughly intelligible" when analysed as a concerto form.

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