John Roeder, "Pulse Streams and Problems of Grouping and Metrical Dissonance in Bartók's 'With Drums and Pipes,'" Music Theory Online 7.1 (2001) << Sect. 4 Section 5a Sect. 5b >> Article Contents

## [5] Pulse-stream Analysis

[5.1] To get a grasp of the analytical method, and to begin to see how it addresses the problems of analyzing polyphony, let us consider Figure 2 in more detail.

[5.2] In addition to the quarter-note pulse stream (1) that we have already discussed, the first block of the passage presents accents every half note. The second and fourth of these accents, corresponding to the dynamically accented downbeats of mm. 23 and 25, are considered in the analysis to mark off a whole-note duration. A whole note later, on the downbeat of m. 27, the reappearance m. 25's verticality creates pulse stream 3. This pulse stream persists through the example. In contrast, pulse stream 2--which in a metric analysis would constitute the strong beats of a 2/2 hypermeter--is created by weaker accents at first. Almost immediately after it is established in m. 25 it begins to deteriorate, and it completely evaporates by m. 30, when no accent at all is provided to sustain it. In the following audio example (V.1), streams 2 and 3 are doubled by low and high cymbals, respectively, and the ascendance of stream 3 over the fading stream 2 is quite vivid.

(Example V.1) [click here for suggestions if the movie does not appear or play correctly]

[5.3] The disappearance of stream 2 signals an important point in the form of the passage, namely, the beginning of the third block of material we identified in our earlier grouping analysis. Analyzing these accents nonhierarchically as the combination of two pulses that vary in presence and strength expresses the continuity and change in the passage better than does either a metrical analysis, which would collapse the two pulses into a simple alternation of strong and weak beats, or a metrical-dissonance analysis, which would recognize the "displacement" dissonance of the two streams (Krebs 1997) but would not account for their changing strength and correlation with the form.

 << Sect. 4 Section 5a Sect. 5b >> Article Contents