Brandenburg Concertos his scoring the concertos for "several instruments" ("Concerts avec plusieurs instruments") is an understatement. Bach used the "widest spectrum of orchestral instruments … in daring combinations," as Christoph Wolff has commented. "Every one of the six concertos set a precedent in scoring, and every one was to remain without parallel." Heinrich Besseler has noted that the overall forces required (leaving aside the first concerto, which was rewritten for a special occasion) tallies exactly with the 17 players Bach had at his disposal in Köthen. Title on autograph score: Concerto 1 à 2 Corni di Caccia, 3 Hautb: è Bassono, Violino
Keyboard concertos by Johann Sebastian Bach timing matched the publication of the first ever collection of keyboard concertos, the widely acclaimed and well-selling Organ concertos, Op.4 of George Frederic Handel published in London and Paris in 1738. The harpsichord concertos were composed in a manner completely idiomatic to the keyboard (this was equally true for those written for two or more harpsichords). They were almost certainly originally conceived for a small chamber group, with one instrument per desk, even if performed on one of the newly developed fortepianos, which only gradually acquired the potential for producing a louder dynamic. The keyboard writing also conforms to a