Bach´s famous Chaconne in d minor (bwv.1004) arranged by Claudio Constantini for bandoneon (originally it´s for violin solo).
 
You can listen to a bandoneon performance here: https://open.spotify.com/album/4LUk9khXDTIzkDRyQ2vQ3x?si=nPyWfWjTRASg75KBUASmGA