The six Brandenburg Concertos BWV 1046-1051, prized jewels of the world's musical heritage, were written in 1721 during Bach's appointment in Cöthen.
Of the six works, Bach originally wrote earlier versions of numbers 1 and 5 which differ not only with regard to articulation but also at times different tones, different rhythms, instrumentation and of course form.
The New Bach Edition is an Urtext edition offering the world of scholarship a reliable musical text which is equally useful in performance. Prepared with the most exacting methods of source criticism, it has set new standards for modern scholarly-critical editions in the latter half of the 20th century.
Work on the New Bach Edition led to the rediscovery of lost compositions and resolved many questions of authenticity in the Bach canon. Most of all, however, the close study of the sources has occasioned a large-scale revision of the chronology of Bach's life, thereby forming the basis for a new image of the composer i n our time.
In each series, the volumes not only contain those works by Bach which have survived intact but also those existing as fragments. In addition to a preface, each musical volume presents a selection of the relevant sources in facsimile.
It is also accompanied by a separately published critical report (German text) describing all the extant sources for each work and the manner in which they interrelate. The report also gathers together all the known facts regarding the work's genesis and lists the most important variant readings.