Audio and Acoustic DNA—Gestalt Theory
While men and women attracted to acoustics are often listeners to classical music and appreciators of visual art, their counterparts in audio are often more fastened on the scientific aspects of the material components used in their work.
Ernst Mach wrote, We do not perceive the world in itself, if we did we would perceive chaos. Thus we have evolved senses that perceive contrasts of perception, relations of perception. Sensations by themselves can have no organic meaning; only the relations of sensations to one another can have meaning.
Perception, Mach believed, is never perception of direct stimuli. Sensations are not simply raw experiences, but the interaction of experience with a preformed cognitive structure. For instance, when we hear a known melody, we recognize it no matter what key it is played in. It can be hummed, buzzed, or strummed on a guitar. Furthermore, even if one or more notes are incorrect, we still recognize it.
Mach asks, What constitutes a melody? It seems incorrect to say that the actual sound vibrations constitute the melody as we have just seen that numerous different sounds can make the same melody. But on the other hand, it seems empirically odd to say that a melody is not constituted out of its sounds. The actual melody, then, exists in our ability to recognize it. It is formed by experience of one or more examples of the melody, but it is an idealization of that experience. Significantly, the idealization captures not the actual sounds, but the relationships of the sounds to one another. For Mach, this process is at the basis of all perception.
Experience requires an “a priori,” but that “a priori” is itself formed by experience. Men and women who have, through experience, learned the deceptive nature of the five physical senses, learn more readily the nuances of acoustic measurements as well as the optimum number and placement of microphones in recording situations. It is the inept in recording work that resorts to close miking and asks “where shall I place the microphone” for a measurement.
They have ears that receive signals but the “listening capability” between them is relatively unprogrammed. There is a great deal of evidence that the current generation in audio have been exposed to highly undesirable “a priori” both in program material and cultural background.
In all professional work one should seek out the real standards that apply which are not necessarily those that are currently in use by the majority. To measure anything meaningfully requires:
1. Experience with similar devices.
2. Mathematical analysis of the device and its most likely performance.
3. Cut and try experimentation.
Obviously the mathematical approach is often the quickest. Experience with similar devices occurs when someone knowledgeable guides you through a process they are already very familiar with. Cut-and-try can overtime, hopefully with a minimum amount of destruction, lead to experience. In the long run, all measurement runs up against a trained listener’s perception. Yes! I know any untrained listener can be satisfied with trash, but any professional’s goal should be acceptance by the trained listener. When that occurs you have gained membership in a privileged peer group.
Ernst Mach 1838–1916, a contemporary of Gustav Fechner the psycho-acoustician, was acknowledged by Einstein as being the philosophical forerunner of relativity. Early in his life Mach defended Christian Doppler against two prominent physicists, Petzval and Angstrom who had challenged the “Doppler effect” by building an apparatus that consisted of a six foot tube with a whistle at one end that rotated in a vertical plane. When the listener stood in the plane of the axis of rotation no changes in pitch could be heard. But if the observer stood in the plane of rotation, fluctuations in pitch that corresponded to the speed of rotation could be heard.
Mach discovered that the eye has a mind of its own; we perceive not direct stimuli but relations of stimuli. The visual system operates through a process of continual adaptation of the present sensation to previous ones. We do not experience reality but rather experience the after effects of our nervous systems adaptations to new stimuli. Our cognitive structure is itself formed through previous experience, and our current experience is structured by it in turn. Mach claimed “We do not perceive the world in itself, if we did we would perceive chaos.” From Gustav Fechner’s work.
Excerpt from Handbook for Sound Engineers, 5th Edition edited by Glen Ballou © 2015 Taylor & Francis Group. All Rights Reserved.
About the Author
Glen Ballou is a graduate of General Motors Institute, now Kettering University, with a bachelor’s degree in Industrial Engineering and a minor in Electrical Engineering. He has been a Syn-Aud-Con representative, has served as governor, convention chairman, papers chairman, and facilities chairman of the Audio Engineering Society (AES), and has been a member for the Society of Motion Picture and Television Engineers (SMPTE). He has been a contributor to S&VC, Sound and Communications, and Church Production magazine on a variety of subjects. Glen also wrote the chapter on capacitors and inductors for the CRC Press publication The Electrical Engineering Handbook. Glen is owner of Innovative Communications, a company that specializes in room acoustics and sound system design.