Taking as a premise the popular theoretical notion that music
(and musical time), at least in "common practice," is organized
hierarchically in a network of interconnected levels, Clarke
wishes to demonstrate that the temporal structures of the various
levels differ from each other in significant ways, both musically
and psychologically, and that these differences have serious
implications for contemporary composers. In tonal/metric music,
the intermediate levels of temporal structure, representing
relationships among single notes or small collections of notes,
and embracing such properties as tempo, proportional durations,
small-scale grouping, and a clear metrical framework, are notated
most explictly in the score. Psychological research into rhythmic
perception is usually concerned with this level, and this
research suggests the primary importance of meter in the
perceptual representation of duration, accent, and grouping
information. Lower levels of temporal structure, involving
minute but systematic variations in timing and duration, are
notated only intermittently or imprecisely and are normally
perceived as expressive or interpretive effects. Higher levels of
structure may continue to manipulate the same properties as
intermediate levels and may be indicated to varying degrees in
the score, but the articulation of grouping boundaries receives
the greatest emphasis and is likely to be conveyed by more
abstract tonal properties. These highest levels are perceived as
the structure of hierarchical relations that we know as musical
form, and since the structures represented are considerably
longer than the perceptual present, their perception must involve
memory processes, facilitated by experience with a musical
idiom.
In Clarke's view the absence of meter in much contemporary music
may have far-reaching consequences, including reducing listeners'
abilities to distinguish musical structure from expressive
transformations (or performance errors) and increasing the
difficulties of establishing stable representations of complex
hierarchic durational structures. Composers need to take account
of these consequences and either provide a framing device such as
meter, or else abandon elaborate hierarchic structure as a
compositional goal and pursue alternative organizing principles.
