24 dic. 2010

Levels of Rhythmic Perception

Imagine a listener, listening to some rather conventional jazz. Imagine that it is me, so I will call him "he."

He perceives the quarter-note pulse. 1 2 3 4 1 2 3 4... These notes are grouped into measures, and those groups are easily perceived too. He has no problem grouping these measures into four- and eight-bar phrases, and these phrases into larger song structures like AABA or the twelve-bar blues.

So he counts four levels of perception: he can easily keep track of the pulse, the measure, the phrase, and the organization of phrases into song-structures. Of course, the actual notes he hears are not just quarter-notes, but whatever notes are actually played, so the fifth level is that of rhythmic detail, the actual swung eight-notes, triplets, etc... that are played, and their relation to the pulse.

These levels can all be perceived easily at the same time because they are hierarchical (smaller units contained within larger) and interconnected. It is not like trying to keep track of five things at the same time, since keeping track of one thing (the pulse say) helps him keep track of everything else.

He can perceive these structures self-consciously, by counting to himself, or simply listen to the music and perceive them unselfconsciously. He could easily teach someone else to hear the music this way as well, if this other person did not already know how. In listening to less familiar genres he does not keep track of things quite as well, but still finds structures more or less "intelligible."

The harmony and melody are also rhythmically, structurally relevant. The listener understands some phrases as answers to others, for example, a falling melodic line as completing a rising one.


Suppose there is an eleven-syllable line that is transparently 11 syllables, like Lorca's "Tu cuerpo fugitivo para siempre." The rhythm is immanent, not concealed. I don't count the number of syllables, but simply fit it into a pattern I have heard many times before. Now take the line "No está en mí, está en el mundo, está ahí enfrente." I accept it as an 11-syllable line in its metrical context, but it is not quite as transparent, because it contains seven elided syllables, with elision crossing over phrasal boundaries. "No es / tá en / mi es / tá en / el / mun / do es / tá ah / i en / fren / te." These elisions of "sinalefas" create stress clashes, with heavy syllables falling on positions 123468910. The metrical accents are on 3, 6, and 10, which makes it a nicely "melodic" hendacasyllable on paper.

So in the prosodic example what is the listener keeping track of? The basic meter, the instantiation of the meter in its actual syllables, and the larger structures. Jack DeJohnette can perform as many metric modulations as he wants, as long as I can still keep track of the pulse, there is no problem.


If I can grasp the basic nature of the problem, then I will already understand it at an advanced level. If I can state the obvious, maybe I can see what is obvious and what is not.