Some of Bach’s extremely popular harpsichord concertos were originally written as concertos for a different solo instrument – the violin or a woodwind instrument. Predecessor versions are also assumed for the f-minor concerto, although they have not been preserved. A very close examination of the sources reveals that the outer movements presumably trace back to a violin concerto in g minor.

However, according to recent research, for the middle movement Bach went back to the slow movement of a...