Bregman’s work on gestalt theory provides a useful tool for understanding compositional choices in my work A Sense of Space. Some key gestalts I drew on are stream segregation, timbre segregation, and gliding tone continuity through noise bursts. Stream segregation refers to the ability to differentiate between high and low pitches and noise concurrently. If pitch or noise is separated into high and low frequency bands, we can hear them as two independent streams (Bregman & Ahad, 1990, p. 11). There are fission boundaries which are the points between the segregation of two or more streams. Within this we have ambiguous regions where it is difficult to determine the identity, so the attention switches between one and two streams. A state called multistability or bistability. Converging and diverging regions are moments of closing and separation of streams.

Separation is strengthened if there is timbral segregation (Bregman & Ahad, 1990, p. 26). Bregman’s studies on pattern recognition shows that when there is rapid movement across the perceptual streams it can be difficult to pay attention to meaningful pitched activities occurring at the same time. This creates the effect of sounds interfering with one another resulting in a blurriness with details potentially missed on first listen. When listening to my piece I am sometimes able to determine the individual timbres of the ensemble. As the speed and the amount of activity increases, I am no longer able to pay attention to all the details that move rapidly through the high and low perceptual streams. A kind of perceptual overload occurs, a mesh of sound.

I intentionally placed two instruments of similar timbre in the same range to create ambiguity of instrumental timbre to encourage misperceptions of listening and the necessity for multiple listens. This occurs where there is an alternation between timbral integration and timbral segregation. A compositional strategy I used is to place two instruments of similar timbre in the same range such as the flute and the high strings of the guitar. The purpose of this is to create ambiguity of instrumental timbre, that can possibly lead to misperceptions of listening, and the necessity for multiple listens to determine what is happening. An example of this is when the crunching sounds of the bamboo masks and distracts the clarity of another instrument. This is comparable to the examples of ‘noise bursts’ given by Bregman who claims that when a sound is followed by a more complex or intense sound the auditory system tries to detect continuity with the preceding sound (Bregman & Ahad, 1990, pp. 60-70). This auditory phenomenon is of interest to create continuity despite surface discontinuities. In A Sense of Space, any loud, short, or relatively complex sound can act in this way, which goes through transformations as timbral variations, nuances, contours, and dynamic expressivity. They act as distractors, focal points of interest, and integrate into larger swarms of activity. Foreground and background features are then distinguished because of the complexity of the sound or noise spectra that masks other sounds momentarily.

(this is a sample of a much larger paper in peer review)

References

Bregman, Albert, and Ahad, Pierre. Demonstrations to accompany Bregman’s Auditory Scene Analysis: The perceptual organization of sound. Montreal: MIT Press, 1990.