Brandenburg Concerto No. 5 "Brandenburg Concertos" takes a central place. Nonetheless around half a dozen of Bach's extant concertos, including some of the "Brandenburg Concertos" and lost models of his later harpsichord concertos, seem to have had their roots in his Weimar period. Most of what Bach may have left with his employer in Weimar perished in a fire destroying Schloss Weimar in the 1770s. In 1719 a new large two-manual harpsichord arrived in the residence of Bach's then-time employer at Köthen. BWV 1050a, an extant early version of the fifth "Brandenburg Concerto", may have been conceived for this instrument, but that seems unlikely
Organ concertos, Op. 4 (Handel) Organ concertos, Op. 4 (Handel) The Handel organ concertos Op 4, HWV 289–294, are six organ concertos for chamber organ and orchestra composed by George Frideric Handel in London between 1735 and 1736 and published in 1738 by the printing company of John Walsh. Written as interludes in performances of oratorios in Covent Garden, they were the first works of their kind for this combination of instruments and served as a model for later composers. Handel's six organ concertos were published in 1738 by John Walsh as the composer's Opus 4. The four concertos HWV 290-293 had been written to