The purpose of the series if Bach was a cellist is to live the fantasy that everything Bach wrote, he wrote for the cello. It may also serve as a way for cellists to get close to Bach through works other than the six solo suites and the three gamba sonatas.
The concerto in D minor (BWV 1043) for two violins, string orchestra and continuo by Johann Sebastian Bach (1685-1750) is one of his most loved works. Indeed, the slow movement may be one of the most popular and loved pieces in the instrumental literature. Traditionally, it is believed to have been written in Köthen, where he held the position of 'fürstlischer Kapellmeister' from 1717-1723, a town that saw the birth of the Brandenburg concertos and the solo works for violin and cello. The Dorian church mode (the absent Bflat in the key of D minor) would also speak for the younger Bach. Recent research, however, has shown that the orchestral parts, carefully written out by Bach himself and found among the papers of his son Carl Philip Emanuel, date from around 1730. The sophistication of the composition also speaks for a later date than Köthen. The original score has been lost.
Always in need of concert material for his 'Collegium Musicus' in Leipzig, Bach made a version of the present concerto for two harpsichords (BWV 1062). The original key was transposed to C minor so that the top note would not exceed a D but remain within the range of a standard harpsichord. Another C minor concerto (BWV 1060) for two harpsi-chords, often heard in an arrangement from the 1920's for violin and oboe by Max Schneider and Max Seiffert, speaks for two concertos in D minor for two violins by Bach.
When arranging an orchestral score for the pianoforte, one has to remember that a double-bass sounds an octave lower than notated. This is a welcomed fact when dealing with two instruments that play the original solo parts an octave down. At the same time, for a transcription of this kind, the ambition must be to avoid the cello soloists playing in octaves with the violin tutti parts - which is what would happen were they to share the same material. This ambition made a piano reduction which is true to the score, an impossible task. In the first movement, it proved necessary to balance the voicing by having the cellists lead the way in the tutti parts. This is, however, not necessary when performing with orchestra, hence the two tutti versions found in the solo parts: one for playing with pianist, the other when accompanied by orchestra. Should the soloists, when occupied with the latter version, wish to leave their concerto grosso duty behind, simply count the rests and play only what is marked solo.
Sources used for my edition are the Eulenburg pocket score series and Bärenreiter's BA5188b as well as its Neue Ausgabe Sämtlicher Werke - the latter resulting, comme l'habitude, in many an hour spent in the Royal Academy of Music reference library. Bach's original dynamics and slurs are found in the piano part. Additional markings in the solo parts are suggestions only.
The idea of a version for two cellos is not a new one. I was 17 years old when I heard it performed by Janos Starker and Maria Kliegel and 25 when I took it on tour with cellist and conductor Mats Rondin. This edition is, with fond memories, dedicated to him.