Clean as a Whistle: Timbral Trajectories and the Modern Musical Sublime

I. Introduction[1.1] This essay considers some expressive aspects of musical timbre.(1) Objectively quantifiable in terms of spectral energy distribution, onset, envelope, and spectral flux, timbre nevertheless remains the most ineffable quality of musical sound, and descriptions of it necessarily resort to terms from other sensory domains: "color," "grain," Klangfarbe, and the like. Its multidimensionality is part of its elusive nature, and while the individual components of a timbre-its attack transients, the synchronicity of its partials, and so on-can be precisely measured, these physical attributes do not always correspond one-to-one with perceptual experience. As contemporary musicians have increasingly focused on timbre as a crucial semantic feature of their work, the need to develop a solid discursive framework for timbre and its effects has become more pressing. My approach in this essay draws on the work of ethnomusicologist Cornelia Fales, whose essay "The Paradox of Timbre" I will quote at some length (Fales 2002). I believe Fales's insights get at the heart of timbre's expressive power, especially her concept of "perceptualization," the notion of timbre as a thing largely forged in the listener's head. While Fales's research interests lie primarily in non-Western musics, I find her work suggestive of an interpretive approach to Western contemporary classical music, an approach that takes seriously associations of transparency and turbidity with pure harmonics and noisy timbres, respectively. The first part of this essay will explore acoustical and psycho-acoustical foundations for those associations. The second part will provide some analytical remarks on selected examples of twentieth-century music in which timbral contrasts of this sort play a crucial role. In particular, I am interested in contemporary works that target sinusoidal purity as a goal within a process of spectral purification. The essay concludes with a detailed discussion of George Crumb's Black Angels.II. Perceptualization[2.1] Critics of ocularcentrism, from Nietzsche onward, have decried our tendency to privilege the visual over the auditory, a tendency reflected in language that equates knowledge with vision ("I see your point") and renders aural information less credible ("hearsay," "word of mouth"). But if we are inclined to characterize vision as the most vivid and active sense, it is in part because the human ocular system is under our motor control: the eyes open and close, isolate and focus, scan across a visual field. No analogous muscle groups are found in the ears-and "no ear lids," as R. Murray Schafer famously put it (Schafer 1977, 11). The ear is not unreasonably construed as strictly receptive, with sound itself figured as the active agent.[2.2] Yet a close inspection of the physiology of the ear reveals a more complex situation. Hearing is not simply a matter of unilateral sound pressure on the auditory nerve, but rather a cascade of intricate electrochemical events within the body. Intertwined with the neural pathways that transmit sounds from the ear to the brain-called afferent pathways-are parallel routes carrying signals in the opposite direction, from the brain back to the ear-known as efferent pathways. These efferent "downlinks" interact with the incoming audio signals in complex feedback loops, and they extend all the way out to the hair cells of the cochlea, where external sound signals initially come in contact with the nervous system. Efferent pathways in other systems of the body are associated with motor neurons: an input signal to the brain induces a motor activity, such as a muscle reflex or a willful physical action. But if the ear is not a "muscle," what possible function could these efferent auditory nerves perform? And what are they doing at the very periphery of the auditory system?[2.3] While their role in human physiology is still not entirely well understood, it appears that the feedback between the afferent and efferent auditory pathways enables a listener to selectively fill in and block out auditory information. …