Polyphony literally means "many voices" [echoed: many voices... many voices...]
As we've discussed so far, a monophonic texture reinforces the melody through doubling
in unisons or octaves, while a chordal texture supports the melody through
harmonization.
In a polyphonic texture each voice is called upon to act in a more independent
manner while still supporting and cooperating with the other voices
involved.
This isn't to say that every instrument should be doing its own thing or that
you have to give each instrument an unrelated melody. In fact, there should be
some thematic, unifying element to the parts, be it rhythmic, harmonic, or melodic,
this commonality will weave a lush, interconnected sonic tapestry and allow
the voices to engage contrapuntally with each other.
Our opening theme, treated in a polyphonic way might sound like this:
Polyphony allows the composer to blur the lines between melody and harmony as
each part can move fluidly back and forth between foreground and supporting
material. The melody can pass through the
instruments, changing register and tambour as needed. This technique was
explored and developed significantly by 20th century masters Arnold Schoenberg
and Anton Webern. They dubbed the term klangfarbenmelodie, "sound-color-melody."
Counterpoint and polyphony go hand-in-hand. Developing your
understanding of counterpoint will deepen your understanding of the fibers
that music is made of. An excellent practice in strengthening the mental
capacity to compose in such a contrapuntal way, which is simultaneously
a horizontal melodic and vertical harmonic process, is through canon, round,
and fugue writing.
In canon writing, the counterpoint must be composed simultaneously with the
melody because ultimately the counterpoint is generated by the melody,
displaced in time, interacting with itself. This means that the melody, in its
construction, has to be mindful of where it will fit in harmonically.
The consistency of tambour across the string section makes it primed for
beautiful polyphony.