Although B-flat major belongs to a relatively subdued key category, we first determine the tempo of this fugue. In cases where no information is available, for example, how should one determine the tempo of a rare Bach work for which it is difficult to find recordings? As one guideline, attention should be paid to notes that are sustained for a long duration.

For instance, in the case of this fugue, the soprano F from measure 22 is tied and sustained until the third beat of measure 24. We consider a tempo at which this F can just barely be perceived as sustained. If the tempo is set too slowly, it becomes unclear whether this F is sounding or not, thus it is advisable to set a relatively fast tempo.

When a fast tempo is set, the ascending sequence in measures 3-4 can, in a positive sense, depict psychological states such as 'heightened anticipation' and 'impatient excitement.' In this regard, this fugue is by no means serious; it would be beneficial to perform it with a cheerful, joyful, and slightly excited disposition.