Trill in Bach fugue WTC 1 BWV 851

Question

In the second bar of the J.S. Bach d-minor Fugue in WTC 1 (BWV 851), we have

How should this trill be played?

Answer 1

According to Bach's father's own Explication concerning the trills and ornaments, we are given a guide on how to interpret the trills. The Expliation was later expanded on by C.P.E. Bach.

There is no question that an historically correct interpretation will start the trill on the upper auxiliary note (in this case the A). The ornament does not descent to an F; there are specific types of ornaments that would require that (like the trillo or the second doppelt-cadence und mordent and the trill is not one of them.

After playing the upper auxiliary note on the beat, you should alternate back and forth between the upper auxiliary and principle notes, playing the principal note at least twice. We are given some suggestions:

1. This suggestion would put a slight rhythmic emphasis on the 5th note in the sequence. For this fugue, that would sound a little awkward. Indeed, in most places in baroque music in general, it would sound awkward, with rare exceptions perhaps (the third beat of a 3/4 measure?).
2. This would allow a smooth trill and also a healthy suspension from the A to the G for the introduction of the theme in the dominant. This would also promote a controlled tempo. I would definitely recommend playing the trill this way for these reasons.
3. This seems at first like it could work, but really the A would be too long. We don't want to emphasize the A, we just want to use it effectively to create tension with the G.
4. If you are playing this at faster tempo, this would be one effective way to execute the ornament.
5. Playing the trill this way would not allow you to play the next note with the Baroque "ordinary touch". In other words, it would be difficult to play it this way and also have the articulation make sense. Also, in reiterations of the fugue subject, it would be tricky to have this done effectively while it is already sometimes difficult to play a trill at all.
6. This way, the trill would not sound like a trill, it would just sound like four 16th notes.

So you have a little bit of artistic freedom. Things to consider are the tempo, the note that comes next, and the context of the piece. Is it consistently playable in places where the subject returns? Does the trill sound uneven played at a fast tempo unless you play it a certain way? You'll hear ornaments in all varieties of music played many different ways in different interpretations. There may be no most correct way, but some ways are definitely more correct than others.

Answer 2

I'm looking at the imslp.org's photocopy of an original score, so I hope I got the right spot (no images allowed thru corporate proxywall :-( ). My guess is to start with the upper note of the trill as a sort of grace-note just prior to hitting the triad; then release the full triad prior to the final sixteenth.

At least, that's how I'd approach a similar figure in Bach's cello pieces.

Answer 3

I've heard this played two different ways:

Option 1:

Option 2:

I believe the first one may be more technically correct, but you'd have to ask a baroque specialist. There may be other options as well, but these should be fairly in-line with the original style.