Johann Sebastian Bach wrote his Trio Sonata for Organ, BWV 528 around 1730, in his early years in Leipzig. The work has also been catalogued as BC.J4. It is a work in E minor, spanning four sections and conceived as an exercise to develop full control of the manual+pedal organ setting, which exerts important technical demands on the performer. In a practice common in the baroque period, Bach actually recycled some of his earlier material in this piece, employing an instrumental trio from the Cantata LXXVI for the first movement of BWV 528.
