Thanks, Dale, for your interesting comments.

>The question remains, in my opinion, *why* Bach preferred to avoid those
>high c#s.  The reason or reasons may have had nothing to do with the compass
>of an expected instrument.

True, although in the case of the B minor fugue from WTC I it is 
precisely something thematic that is altered, and that makes it all 
the stranger and implies that Bach must have had some fairly 
compelling reason.

>A similar example, also in b minor, is the organ prelude & fugue BWV544.
>Toward the end of the fugue Bach makes an alteration of the countersubject
>which avoids the high c#.  In my opinion he may have wished to avoid this
>note for "purely musical" reasons, by which I mean that he possibly
>preferred a more gradual and uninterrupted descent from the high b, maybe as
>a means to achieve a more convincing closure.

True. But this is an opinion. In the Prelude to the same work, he 
conspicuous avoids the low C sharp octaves in the pedal line (they 
were missing on many organs at that time), despite thereby creating 
some uncomfortable gymnastics of an unusual kind for the player.

For my Harmonia Mundi recording of the WTC, I of course played the 
standard text. But in performance, in concert, I sometimes restore 
these "avoided" notes, because I have an on-going dialogue with these 
measures. Can I find other reasons why there might have been 
something purely musical that was "wrong" with them? (So far, I 
can't.) I often play the low C sharps in the organ prelude, if they 
sound OK on the organ I'm playing and in the acoustic at hand. I 
usually don't alter the B minor fugue from WTC I because this is not 
just octave transpostion, the musical line was rethought by JSB, so 
that does seem interesting and valid as a text.

In WTC I, in the D sharp minor fugue (that appears almost 
incontrovertibly to have been transposed up from D minor), the 
peculiar, irregular counterpoint surrounding the curious tied high B 
natural (measures 15-16), where the counterpoint and the melody 
naturally ought to go up to C sharp, makes sense if we assume this 
passage (in D minor) did indeed go up to a high C, and should 
therefore have been high C sharp in the transposition. But Bach, at 
the expense of breaking the rules of counterpoint with a very unusual 
dissonance that is resolved in an irregular manner, leaves the 
version we all know. The reason for doing this must have been 
extremely compelling indeed.
Note: two sources for the 48 do give the high C sharp here: the J. G. 
Walther manuscript copy (Berlin SPK Mus. ms. Bach p 1074); and the 
printed edition edited by Forkel (Leipzig: Hoffmeister, 1801).

>The temptation to think "Bach wrote this, so he must have
>meant/wanted/intended such&such" is great.  Davitt expresses himself more
>circumspectly.

Circumspection can be frustrating in the short term, but is necessary 
(and occasionally a great relief) in the long term...

DM

-- 
Davitt Moroney
Professor of Music; University Organist
Department of Music, 210 Morrison Hall
University of California, Berkeley, CA 94720-1200, USA
email: [log in to unmask]
Office:  +1-(510) 643-4580 / Fax: +1-(510) 642 8480
http://music.berkeley.edu/Moroney.html