...These new editions were based on surviving autographic source material - some of which, for the Fifth Concerto for example, has been taken into account for the first time - and the 'Neue Bach-Ausgabe' (NBA). Moreover, they also make use of relevant 18th-century theoretical writings for editorial additions and observations on performance practice.”(from the joint preface to the “Six Brandenburg Concertos” by the Bach scholars Werner Felix, Winfried Hoffmann and Armin Schneiderheinze)