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Pérotin: Excerpt from “Viderunt omnes” (c. 1200)

From the album Pérotin - The Hilliard Ensemble

One of the earliest composers we know by name, Pérotin was a prominent figure in the so-called Notre Dame school of music, which flourished in Paris around the year 1200. Pérotin and his younger contemporary Léonin composed one of the earliest forms of notated polyphonic music, a genre known as organum.

The form of Notre Dame organum—and thus the distinctive sound of the music—rests upon a remarkable structural conceit. The lowest voice in the texture (the cantus firmus or fixed voice, which forms the harmonic foundation) sings notes drawn from fragments of Gregorian chant, but stretched to extremely long durations, many hundreds of times their original length. With these sustained tones as the basis, the upper voices sing newly composed melodic filigrees in a quick triple time (known as tempus perfectum, in analogy to the Trinity). There are also brief passages of discant, in which all voices move in rhythmic unison, creating a lighter and more active texture.

First page of the original notation for Viderunt omnes

The sound of this music is striking not only because of the intense droning of the cantus firmus, but also because of the timbral changes that take place with each new syllable in the bottom voice. When this voice changes its pitch, it also changes its syllable and thus its vowel, creating a remarkable acoustic effect that could be compared to the changing of perspective or lighting in the visual field.

(You can experiment with this yourself, singing a continuous pitch and changing from “ah,” “eh,” “ee,” “oh,” “oo” to hear how the timbre of your voice changes. As you sing each vowel sound, your vocal tract is functioning as a complex filter to shape the vibrations generated by your vocal folds.)

In this example, the first such change takes place about one minute into the piece. The second change, about 30 seconds later, coincides with a shift toward a darker, “minor” modality (the term is anachronistic here), creating a wonderful effect that is totally unique to this music.

If you listen closely, you can hear that the cantus firmus very slowly moves through the syllables of the phrase “Viderunt omnes” (Latin for “all the world has seen”) over the course of the first four minutes of this excerpt. Afterward you hear the monophonic Gregorian chant from which the cantus firmus is derived.

Played 303 time(s).

August 25, 2011, 9:04pm

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