Davitt wrote, among other interesting observations, the following:
----- Original Message -----
From: "Davitt Moroney" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Monday, September 11, 2006 7:25 PM
Subject: Re: "Bach harpsichords" ?
> Bach's keyboard ranges are instructive:
> -- WTC I (1722) is strictly 49 notes, four chromatic octaves (this
> need not be just because he was thinking of a little clavichord).
> That this is not a coincidence is shown by the fact that he twice
> deliberately mistreats the countersubject to the fugue in B minor to
> avoid high C sharps. [....]
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.
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. A high c# might possibly have
been perceived as too prominent, in his composer's ear, at this point in the
piece. [The high b is approached as a fairly spectacular dissonant seventh,
and the resolution to a may have seemd too important to permit the intrusion
of the high c#.]
We can only speculate as to why he chose this solution, which has indeed
both advantages - if indeed one considers them to be advantages. Whether an
18th-century player using an instrument with a high c# would have found
Bach's "solution" to what he saw as a non-existent compass problem to be an
improvement, we'll never know.
The temptation to think "Bach wrote this, so he must have
meant/wanted/intended such&such" is great. Davitt expresses himself more