Both in theory and practice, listening is the crucial interface between the individual and an environment. It is also a set of sophisticated skills that appear to be deteriorating within the technologised urban environment, both because of noise exposure, which causes hearing loss and physiological stress, and because of the proliferation of low information, highly redundant, and basically uninteresting sounds, which do not encourage sensitive listening. To understand the basis of acoustic communication, we need to examine the nature of listening more carefully. 

It is interesting to speculate as to why the human auditory system evolved this kind of sensitivity to physical vibration within a certain range of frequencies and a large range of intensities. In the case of the visual system, it seems more than coincidental that the range of visible frequencies, out of all those present in the electromagnetic spectrum, is centred on one of the fairly narrow bands that the earth's atmosphere transmits. [...] The extremely small wavelength of light allows it to reflect off objects and convey information about the most minute characteristics of the object, such as colour and texture. [...] Because of the extreme speed of light, all such detail seems to come to us instantly, giving an immediate 'report' of the details of an environment.

Sound vibration, by contrast, requires physical objects and a physical medium of transfer. Moreover, it is quite slow [...]. Whereas vision allows us to scan an environment for specific detail, hearing gives us a less detailed, but more comprehensive, image of the entire environment in all directions at once.