Fugue: Exposition

Back to Music 103 home page...

Definitions: Exposition, Redundant Entry, Counterexposition

Exposition
The initial section of a fugue, where each voice presents the subject in turn--either in its original or its answer form--is called the exposition. The subject is presented as many times as there are voices contained in the fugue. In order that the first two entering voices sound like a closely associated pair, they are generally presented registrally close together, in adjacent voices (e.g. soprano and alto, alto and tenor, or tenor and bass).

Redundant Entry
Occasionally, the exposition contains one extra entry, called a redundant entry, as in WTC 1, the 3-voice fugue in D# minor (4th entry in m. 12 is redundant ), and the 3-voice fugue in Bb major (4th entry in m. 13 is redundant).

Counterexposition
Sometimes, too, a second exposition follows immediately after the first one. The second one is called a counterexposition, where the voices generally enter in a different order than in the first. The F-major fugue from WTC 1 features a counterexposition that begins in m. 18. The order of the 3 entries there is soprano, alto, bass, while the order in initial exposition is alto, soprano, bass. The G-major fugue, WTC 1, has a counterexposition beginning in m. 20, where the subject is presented in inversion!

Harmonic Design
As a rule, the subject entries in the exposition alternate between tonic and dominant. The harmonic design of the exposition in a 3-voice fugue is I-V-I, in a 4-voice fugue, I-V-I-V. Examples from WTC 1 are, among many, the 3-voice fugue in G major (I-V-I, mm. 1, 5, and 11), and the 4-voice fugue in G minor (I-v-I-v, mm. 1, 2, 5, and 6).

There are exceptions to this harmonic order, however, as in the 4-voice C-major fugue, WTC 1, where we find I-V-V-I (mm. 1, 2, 4, and 5).

Modulatory Link
As pointed out in the discussion of the answer, the second entry in a fugue is in the dominant--a transposition up a fifth from the first entry. The answer routinely starts in the tonic, but very soon shifts to, continues in, and ends in the dominant. If the third voice is to enter in tonic, completing the overall I-V-I progression (see above), a modulatory passage is necessary--a modulatory link--between the end of second entry (the answer, in dominant) and the beginning of the third entry (in tonic). This is especially so when the subject begins on scale degree 1, since the tonic note cannot enter as the answer ends, where the dominant key prevails.{1}

The C-minor fugue (3-voice), WTC 1, has a modulatory link in mm. 5-6, between the 2nd and 3rd entries. The Ab-major fugue (4-voice) has a link in mm. 3-4.

If the fugue subject begins on scale degree 5, the third (tonic) entry could begin immediately, right as the answer ends. No modulatory link leading back to tonic is necessary because scale degree 5 is consonant with dominant harmony, which prevails when the answer ends. The C#-major fugue, WTC 1, illustrates the case. Its subject begins on scale degree 5. The answer ends in m. 5, in the dominant, and the 3rd entry sets in almost immediately (bass). The Bb-major fugue does the same thing (see m. 9).

Sometimes, even when the subject begins on scale degree 5 and a modulatory link is unnecessary, we find one anyway, as in the Eb-major fugue, WTC 1. This exposition is particularly curious because the answer does not even end in the dominant. It begins in the dominant, as usual, but then modulates back to the tonic, so that the third entry could easily have begun right away (middle of m. 4)! Instead, we encounter a modulatory link in the latter half of m. 4. It continues through m. 5 before the 3rd entry finally appears in m. 6.


1. In the C-major fugue of WTC 1, there is no modulatory link between the second and third entries, even though subject begins on scale degree 1, because the third entry is in the dominant, not tonic. [Back to text...]

Back to Music 103 home page...