The original source for these transcriptions is Bach’s autograph manuscript. In the “Literal Transcription” this manuscript has simply been copied and transposed down a fifth (plus an octave). All the bowings in the “Literal Transcriptions” are Bach’s. In the “Edited Concert Versions” however, Bach’s bowings have very often been changed.
This movement is almost constantly in doublestops and chords. Of its 141 quarter-note beats, no less than 121 (more than 85%) have at least one doublestop or chord on them. In fact 85% of all the notes in this movement are part of either a doublestop or a chord. In spite of this densely chordal nature, surprisingly only six chords have needed to be revoiced to make them possible for the cello (in bars 9, 22, 24 and 33).
Probably the greatest difficulty of adapting this Adagio to cello is actually its very low register, the highest note being only an Eb on the A-string. This low register, combined with the constant double-stopping and chords makes it a prime candidate for playing as a cello duo, transposed up a fifth (into the original violin key). It really does sound a lot better in this way, played in the original key by two cellos rather than transposed down a fifth for one solo cello. But even after distributing all the notes between two cellos, there is still the need for frequent double and triple-stopping. Because of this it is actually the three-cello version that gives the best results: now all the harmonies can be played completely free of all tension. One wonders why Bach didn’t just write this piece for string orchestra from the beginning! No additional notes have been added to these duo and trio versions apart from an optional harmonisation of bars 12 and 45-46.
This is the longest of Bach’s solo violin fugues, and like the others, is intensely polyphonic (with many doublestops and chords). Even when we divide the notes of these polyphonic passages between two players (in the “Duo Version”) we still sometimes have too many notes to play. To be really comfortable, we would need to make a version for three cellos, but then the third cellist might go to sleep in those non-polyphonic passages where there is nothing for them to do!
Approximately 40% of the quaver beats in this movement have at least one doublestop or chord on them, which makes it a good candidate for playing as a cello duo. In our “Duo Version” the second cello has an accompanying voice, playing all the lower notes of the doublestops and chords as well as those other harmony notes that we have filled in in where Bach left the harmony “empty”. The Duo Version in the “cello key” (transposed down a fifth) will thus also be our “Easier Version”. Playing this movement as a duo makes it so much easier that, as with many other of the Duo Versions of movements of the Bach Unaccompanied Violin Partitas and Sonatas, we can play it now also in the original key (one fifth higher than the “cello versions”).
This movement presents a layout dilemma: on one page it is quite cramped, on two pages it is very spread-out, and it is not possible to combine it with either the preceding or following movements. Faced with an impossible decision, it is offered her in both layouts: wide-spaced (2p) or tight (1p).
Low Duo Version (down fifth): Unedited Low Duo Version Down fifth): Edited
This movement adapts very well to the cello. It has absolutely no doublestops or chords, which certainly helps for the adaptation process. No notes have needed to be changed from the violin version, although many bowings have been slightly modified to suit the cello better. Of the 1196 notes in this movement, 2 are quarter-notes, 24 are eighth-notes and the remaining 1170 (98%) are sixteenth-notes. This could easily produce the “sewing-machine effect” but doesn’t, thanks to the great variety of imaginative bowings and string-crossing effects that Bach uses. This movement goes as high as Bach ever takes us in his unaccompanied music: up to “C” on the A-string. It not only takes us up high, it also keeps us there for a good while of climactic high-register thumb-position scrubbing: a fitting climax for the final movement of his last Solo Sonata.