text: The first piece in this collection closes with a minuet that alternates with a polonaise and two trios.
full_question: The first piece in this collection closes with a minuet that alternates with a polonaise and two trios. The second piece in this collection features a solo trumpet using the high-pitched clarino register. The fourth of these pieces prominently features a violin and two flauti d'echo, which are usually replaced with recorders. In the middle of the first movement of the fifth of these pieces, the other instruments drop out to leave the solo harpsichord with a lengthy cadenza. Each piece in this 1721 collection calls for a group of solo instruments to be backed by the larger orchestra. For 10 points, name this set of six pieces written by J.S. Bach for the title German margrave.
first_sentence: The first piece in this collection closes with a minuet that alternates with a polonaise and two trios.
raw_answer: Brandenburg Concertos [or Six Concerts Ã  plusieurs instruments]