here's an example. 3rd beat, Bach has the cello dip down to D. The note is clearly part of the "bass", but also functions as an octave displaced continuation of the melody, as part of an arpeggiated G chord, and even as a simple melodic jump of a 7th. Only the D can evoke all of these at once.
Yates isn't necessarily wrong to arrange it his way. Once you have filled out a bass line, the D is likely to create ambiguity, so using the G instead might be reasonable. Perhaps he should allow the high line to continue up to D instead of down to B, but there are going to be compromises when transforming music this way.
The problem is that for anyone who knows the cello suites, that drop of a seventh causes pleasant invocations of memories and triggers those grand old neurons, regardless of the functional harmony at work. Beyond that, the real joy of the piece is the way that Bach composes through the limitations of the cello to create something unlike anything else - to lose that is to lose the reason for playing these works in the first place.
Another point of interest is in the next measure. Bach suspends the statement of the C, stretching it over the measure, at the same time changing the texture.
Now, if you're adding a bassline, you probably have to do something on the first beat, or risk sounding thin and lost. And it is a resolution to the tonic, so the C is a likely choice. Perhaps some motion in octaves would work, or maybe an A minor feeling. In any event, the presence of a bass note on beat one weakens the feeling of the descending line.
Then, it also loses the E D C descending line found in the third beats of mm 2-4. The is the D I mentioned earlier on the 3rd beat of m3, and a similarly placed E in m2.
These kind of structural motions are all over the cello suites. I actually arranged the whole 4th cello suite, and I'm a little happy with it, but I scrapped it because I felt that the likelihood was that I was not even seeing the most important aspects of the work.
I'm going to take a look at the Duarte again - I love his compositions.
Last edited by Brian Brock on Thu May 03, 2012 5:35 pm, edited 1 time in total.