Originally, the two-part pieces were entitled "Praeambulum" and the three-part "Fantasia"; they were part of the Klavierbüchlein für Wilhelm Friedemann Bach of 1720. In 1723, Bach wrote them down again in a fair copy - in a new arrangement and with the new title, with numerous additional ornaments and a few corrections or rhythmic changes. In addition, there are two copies, one by an unknown Bach pupil probably around 1723, and one by Heinrich Nikolaus Gerber from 1725, both of which are richly ornamented.
In his fair copy of 1723, Bach arranged the inventions and symphonies in ascending order of key. In contrast to the "Well-Tempered Clavier", there are no pieces in the keys that were uncommon at the time.
The inventions and symphonies are not only occasionally played pieces, but mainly practice works for players and model instructions for composing; they are also contributions to a philosophy of music. They contain numerous examples of contrapuntal composition.
This piece is "almost" played live, I only changed the tempo and cleaned up some unclean parts, so that a homogeneous overall picture was created.