1. Bach’s Brandenburg Concertos are fine examples of the concerto grosso, as Vivaldi’s are of the solo type. Eventually the concerto grosso lost ground to the solo type. Vivaldi has a direct connection with the classical era through the influence of his solo concertos. A good classroom activity would be to generate a brief discussion about the two listening examples. Why did the solo concerto prevail over the concerto grosso (represented by Brandenburg no. 5)?
2. Each of Bach’s six Brandenburg Concertos has differing instrumentation. Some use recorders, some flutes. Some have brass instruments, others not. The reason was to provide as much contrast within the concertino as between it and the ripieno. It was not until the mid-eighteenth century that the instrumentation of the orchestra became somewhat stabilized.