The music to cantata BWV 205a is lost but all the movements except the recitatives 8, 12 and 14 (which were newly composed) were parodied from BWV 205 in order. So, in structure, BWV 205a sounds very like BWV 205. For more details, see the critical commentary of NBA I/37. I'm not aware of any recordings of this possible reconstruction.
Copyright © 1998, Simon Crouch.