Imitative Polyphony PODCAST
A musical texture featuring two or more equally prominent, simultaneous melodic lines, those lines being similar in shape and sound.

Polyphony is usually divided into two main types: imitative and non-imitative. Either the various melodic lines in a polyphonic passage may sound similar to one another, or they may be completely independent in their rhythm and contour. If the individual lines are similar in their shapes and sounds, the polyphony is termed imitative; but if the strands show little or no resemblance to each other, it is non-imitative. Each of these types may also mix with or succeed one other in a musical passage.

In contrast to the independence of the musical lines in non-imitative polyphony, imitative polyphony allows the members of a polyphonic texture to share audible features of the melodic material, as they echo portions of it among the various parts.

Although imitative polyphony may appear in music from a variety of cultures, it is particularly prominent in Western European art music. Similarly, although it appears in medieval compositions from as early as the 13th century, imitative polyphonic textures were especially exploited in music from the later Renaissance and the Baroque periods, from approximately 1500-1750.

In the following example of imitative polyphony--a vocal composition from the Renaissance written by Josquin des Prez--each of the four voice parts begins successively with the same musical phrase. This opening phrase begins alone in the highest of the parts, and then works its way down to the lowest voice in the texture. Each of the entering voices thus imitates its predecessor as it presents its material.

[Example 1: Josquin, Ave Maria, Virgo Serena, stanza 1]

But significantly, after each of the parts has sung its opening phrase, it does not resort to accompanying material; instead it continues to spin further melodic phrases that are also taken up by each member of the ensemble in turn.

As a result, each of the four participants in this texture retains its musical identity and interest throughout this section of the piece--they all are thus truly polyphonic. And, since each of the parts also recalls the others with similar sounding material, the polyphonic texture is imitative.

The same principles of sharing musical material among the various melodic lines can be heard in these two selections from instrumental compositions by the Baroque composer J.S. Bach. As in the previous example, each part enters individually with a similar musical phrase, and then continues to act as an important participant as the piece progresses. The first example shows the procedure in an orchestral context.

[Example 2: J.S. Bach: Third Orchestral Suite, "Overture"]

The second demonstrates imitative polyphony in a piece for solo harpsichord, played by a single performer.

[Example 3: J.S. Bach: Well-Tempered Clavier, Book 1, Fugue no 2 in C minor (opening)]

Summary:

• Polyphony may be imitative or non-imitative, depending on how closely the various musical lines resemble each other.
• If the individual lines are similar in their shapes and sounds, the polyphony is termed imitative;
• but if the strands show little or no resemblance to each other, it is non-imitative.
• Each of these types may also mix with or succeed one another in a musical passage.
• Imitative polyphony is associated particularly with Western music from the later Renaissance and the Baroque periods.