La CPFH y la Feria Permanente

EXAMPLE 9–2(b)

EXAMPLE 9–3

Messiah(Part Two), No. 44 “Hallelujah!” G. F. Handel

The familiar passage shown as Example 9–3 illustrates a procedure known as tonal imitation. The alto voice presents the theme beginning on the note A, the dominant note (5^) of the key of D. The soprano answers with a slightly different version of the theme: it begins on the tonic (1^) a perfect fourth above, but thereafter is transposed to the perfect fifth above, so that the remainder of the theme is, considering the alto’s G

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in measure 50, essentially in the secondary tonal region of the dominant, A major. If the answer had begun on the note E, rather than D, the transposition could have been exact throughout. Why the change of the first note from E to D?

The answer to this question lies in the fact that Baroque composers (unlike their Renaissance predecessors) were interested in establishing the key and mode of a piece from the start. With very few exceptions, if the subject begins on the dominant of the key, the answer will begin on the tonic and vice versa. The remainder of the theme will occur in the temporary key of the dominant. Thus, although the two keys are contrasted during the initial bars of the piece, the principal key is clearly marked at the start by the initial notes 1^ and 5^, or 5^ and 1^.

We can summarize the two essentials of tonal imitation like this:

1. In order to help establish the principal key of the piece clearly, the opening notes of subject and answer are 1^ and 5^. Should both 1^ and 5^ occur very near the opening of the subject, the answer will reverse these to 5^ and 1^.

2. The answer transposes the subject from the tonic key to the dominant key.

Returning to the C-minor Fugue from Bach’s WTC I (Example 9–1), the second voice to enter is the soprano (S) (mm. 3–4). Compare it with the original entry in the alto (mm. 1–2). You will see that the fourth note in the original version of the subject is the note G (scale-degree 5^). This is answered by the note C (scale-degree 1^), a perfect fourth above. However, the remainder of the theme is transposed up a perfect fifth, maintaining the dominant key. Thus, not all dominant notes in the subject are to be answered by tonic notes, only prominent 5^s that occur near the beginning, because otherwise the characteristic features of the subject might be altered. For example, if every scale-degree 5^ were to be answered by a 1^, the result would be to destroy the inner line descent from E

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through D to C. (See Example 9–4.)

EXAMPLE 9–4

Hypothetical answer to subject from WTCI, Fugue No. 2 in C minor

The Modulating Subject

Although these rules for tonal imitation suffice to explain the situations in the examples from Bach’s C-minor Fugue and from Handel’s Messiah, the situation is not that simple in every case. For instance, a subject may begin in the principal key but modulate to the secondary key of the dominant, employing the raised scale-degree 4^. This is referred to as a “modulating subject.” In such cases, the answer must begin on the dominant and move to the tonic; the theme must be transposed up a fourth at a suitable point rather than the usual up a fifth (otherwise, the answer would end in the supertonic key). Example 9–5 demonstrates.

The subject of this choral fugue, presented as Example 9–5(a), introduces the secondary tonal region of the dominant, A major, in measure 3. If the answer were to transpose the theme up a perfect fifth, the result would be a move to the supertonic, a key that would not be desirable so close to the beginning of the piece (see Example 9–5(b)). The version shown as Example 9–5(c) attempts to transpose the last two measures plus the pickup to the tonic key. This version is clearly unacceptable, however, since the drive upward from the opening note (A) has only a fourth rather than a fifth (as in the subject version) to travel. The result is the awkward “bump” at the end of the second measure: the anticipation on the note D. The standard solution in themes of this type—where there is an upward ascent of a fifth—is what Bach uses here: namely to begin the ascent later, so that the pitch of the first note is repeated before beginning the climb (see Example 9–5(d)).

Before reading on, write answers to the following subjects, applying the strategy of the delayed ascent.

EXAMPLE 9–5

Magnificat in D major, BWV 243, No. 11 “Sicut locutus est” J. S. Bach

In both cases, the correct answer will repeat the opening note before going on to transpose the subject a perfect fifth below in the first case and a perfect fourth above in the second case. Double- check your use of accidentals, especially in minor keys. When answering the C

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-minor subject, every note after the first one must be transposed by exactly a perfect fourth, which will require the use of certain accidentals: the D on beat 4 of measure 2 will have to be “naturalized” (because of the D

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in the key signature) and the penultimate note will have to be a B

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(to produce a leading tone in the tonic key).

The Modulating Subject with Scale-Degree (

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)7ˆ

Example 9–6 shows a modulating subject with its answer.

EXAMPLE 9–6

WTCI, Fugue No. 18 in G

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minor J. S. Bach

This subject, like many of Bach’s modulating subjects, includes a leading tone very near the beginning. In a case like this, it is quite easy to write a proper answer simply by beginning the transposition up a perfect fourth at the point that corresponds to the 7^ or

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7^ in the subject. Thus 7^ (the third of the dominant chord) is answered by 3^ (the third of the tonic chord). In minor mode, the

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7^ is answered by

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3^. The remainder of the theme is left intact so there is little danger of altering a characteristic feature of the melody.

Before reading on, write the answer to the following subject:

Since the subject begins with 1^–5^, the answer must begin with 5^–1^. The third note of the subject,

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_{7^, is answered by}

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_{3^, and from there on the answer is at the perfect fourth above, allowing it to move} to the tonic key rather than to the supertonic (as it would have done if the answer had been at the perfect fifth above). Thus:

Answering 7ˆ with 3ˆ in a Non-Modulating Theme

Scale-degree 7^ is occasionally answered by scale-degree 3^ even when the subject does not modulate. In the theme given as Example 9–7, the second note (G

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) is scale-degree 7^ in the key of A major. It is answered by scale-degree 3^ (C

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). The third note leaps up a perfect fourth—a characteristic of the melody. For that reason this perfect fourth must be maintained in the answer, but the remainder of the theme can be transposed up a perfect fifth, as usual.

EXAMPLE 9–7

WTCI, Fugue No. 19 in A major J. S. Bach

The Answer by Real Imitation

Not every theme requires both a subject version and an answer version. If a theme does not modulate and if it lacks a prominent 5^ near the beginning, as in Example 9–8, the answer is a simple transposition to the secondary tonal region of the dominant. In a case like this, we refer to the answer as a “real answer” rather than a “tonal answer.”

EXAMPLE 9–8

WTCI, Fugue No. 1 in C major J. S. Bach

In document SEGURIDAD Y SOBERANÍA ALIMENTARIA Y NUTRICIONAL EN CIUDAD DEL ESTE ACCIONES Y POLÍTICAS PÚBLICAS (página 51-57)