Piano concertos by Wolfgang Amadeus Mozart it was probably J.C. Bach, whom Mozart admired, who introduced the structural innovation of allowing the keyboard to introduce new thematic material in its first entry. Concertos Nos 1–4 (K. 37, 39, 40 and 41) are orchestral and keyboard arrangements of sonata movements by other composers. The next three concertos (K. 107/1, 2 and 3), which are not numbered, are arrangements of piano sonatas by J.C. Bach (Op 5. Nos. 2, 3, and 4, all composed by 1766). Based on handwriting analysis of the autographs they are believed to date from 1771–72. Concerto No. 5, K. 175 from 1773 was
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