Meter (music) - Metric Structure

Metric Structure

The definition of a musical meter requires the identification of repeating patterns of accent forming a "pulse-group" that corresponds to the poetic foot. Normally such pulse-groups are defined by taking the accented beat as the first and counting the pulses until the next accent (MacPherson 1930, 5; Scholes 1977). Normally, even the most complex of meters may be broken down into a chain of duple and triple pulses (MacPherson 1930, 5; Scholes 1977). The level of musical organisation implied by musical meter, therefore, includes the most elementary levels of musical form (MacPherson 1930, 3).

The general classifications of rhythm metrical rhythm, measured rhythm, and free rhythm may be distinguished in all aspects of temporality (Cooper 1973, 30). Metrical rhythm, by far the most common in Western music, is where each time value is a multiple or fraction of a fixed unit (beat, see paragraph below) and normal accents re-occur regularly providing systematical grouping (measures, divisive rhythm), measured rhythm is where each time value is a multiple or fraction of a specified time unit but there are not regularly recurring accents (additive rhythm), and free rhythm is where there is neither (Cooper 1973, 30). Some music, including chant, has freer rhythm, like the rhythm of prose compared to that of verse (Scholes 1977). Some music, such as some graphically scored works since the 1950s and non-European music such as Honkyoku repertoire for shakuhachi, may be considered ametric (Karpinski 2000, 19). Senza misura is an Italian musical term for "without meter", meaning to play without a beat, using time to measure how long it will take to play the bar (Forney and Machlis 2007,).

Metric structure includes meter, tempo, and all rhythmic aspects which produce temporal regularity or structure, against which the foreground details or durational patterns of any piece of music are projected (Wittlich 1975, chapt. 3). Metric levels may be distinguished: the beat level is the metric level at which pulses are heard as the basic time unit of the piece. Faster levels are division levels, and slower levels are multiple levels (Wittlich 1975, chapt. 3). A rhythmic unit is a durational pattern which occupies a period of time equivalent to a pulse or pulses on an underlying metric level.