With all due respect to, and without even a distant thought of denigrating the efforts of those stalwarts whose efforts have advanced the state of the art and science of measurement to what it is at the present, permit me to present the following.
Measurement has been at the core of understanding the environment, be it the visual or the auditory, or for that matter, any other. Over the decades, a fuller understanding of the acoustical environment had necessitated the use of various tools to measure acoustical events and classify their characteristics as a first step towards that aim. However, there appears to be as much disagreement as there is agreement in what to measure and how to measure. There is also the possibility of other dimensions, other parameters existing, which do not easily lend themselves to our known tools of analysis. A sane approach, it is evident, would accept that measurement and understanding is a classic "chicken and egg" situation at best. How could you measure without understanding, and how could you begin to understand without measurement?
History is full of instances of inspired surmises that led to both an initial conceptual understanding and subsequent measurements that led to a finer distillation of both the original concept as well as the tools of measurement. In order to approach the concept of measurement in as dispassionate a manner as possible, particularly in a field as passionate as sound and music and its reproduction, one needs to take a second look at distant cousins of measurement.
In the near past the standing joke about Relativity was that only a couple of people understood it clearly--Einstein, of course, and then God! In today's world how many people have a grasp of the dozens of dimensions beyond the third and the fourth that a respected master mind like Stephen Hawking proposes? We wouldn’t be far from the truth if we repeat that only a couple of people understand that too! That should tell us that what we hold as supreme truth appears to be so only because of our ignorance of "other truths", other dimensions.
In the context, it will be interesting to look at another classic urban legend about the dozen, fifty or even hundred words (depends on your viewpoint) that the Inuits and Aleuts have for describing snow. (http://www.putlearningfirst.com/language/research/eskimo.html) English too has its share of related words--powdery snow, sleet, slush, flurry, blizzard... When we see water, our reaction could be anything from water to lake to pond to river to ocean, and then some. Our understanding of the environment calls for an ability to 'measure' and classify what is around us. The different words for snow, and water, be it in English or Inuit, is an attempt at ‘measurement’ as a way of identification, classification and understanding.
A personal experience of mine from some years ago could be read in conjunction with this to explore the concept of 'measurement' from another angle. When a fishing boat belonging to a friend who owned a small fleet failed to return to harbour, a 'search and rescue' mission was launched. I, emboldened and sustained by little more than over-enthusiasm, jumped at the opportunity to join them for an all-night chase in the seas. As the small boat with a couple of outboard engines (for speed!) chugged out, I Iistened in on the hurried consultation among the crew and their skipper. They were talking about 'places' in the wide open sea the way we would mention the street corner near our home, or the big intersection near the park or maybe the turnoff in the highway. Using dead reckoning and a simple compass, they set course and we sped on for a couple of hours. I asked the (foolish) question why we were not keeping the search light switched on. The answer was a flip of the switch and a question directed at me about what I could see. With chagrin I realized that the "illuminating" light confused me by what it revealed of the endless rollers and the dark vastness of the sea. My measure of a 'logical' action did not apply here. As the night wore on, we spent hours zigging and zagging first to one 'location' and then to another. The language in which the “old salts” communicated told me nothing, but it made perfect sense to them. At long last they tried an unlikely location and we were able to "raise" the lost boat, which was drifting with a dead engine.
Translate this scenario into a modern setting with all boats equipped with GPS and communication gear. The GPS gives you accurate 'measurements', and your navigational 'measurements' would zero you in on the target in a matter of time. But what had happened in the pre-GPS days was another way of more or less accurate 'measurement', which too produced results, and that too with very few inputs! From dead reckoning and a compass we have come a long way to the GPS. But that doesn’t prove that the GPS is the only form of accurate measurement. It also doesn't prove that the GPS is the ultimate. Where are we headed technologically in the post-GPS days? The great seafarer-anthropologist Thor Heyerdahl had time and again paid glowing tributes to the navigational 'measurements' of the Polynesian islanders who were total strangers to the European navigational methodologies. For arguments' sake you could say that they were "not right", but we have to admit they were and they sailed the vast oceans with more daring and confidence than many, thanks to their little-understood ways of 'measurement'.
If you have come this far, you are in some agreement that measurements, in its varied guises, are at best a complex and vague (until you have mastered it, that is!) territory, though we all agree that they are central to understanding.
Our interest in an acoustic event has come way beyond its primary function of relating ancient man to his environment by serving primarily as a warning signal. This was the reality of prehistory when man lived as a hunter in a variety of physical environments. Evolution has equipped man with a hearing mechanism that can present a rich data flow to his brain and give him accurate visualizations of his environment. Ever since Thomas Edison realized his dream of “canning” an acoustical event, man has been facing the dilemma of what to capture and what to throw out in order to maintain what each generation thinks is 'fidelity'. Nobody who has listened to an early recording would consider it as having any 'fidelity' whatsoever. But to the early listeners of this wonder, it sounded "life-like". Obviously the ‘measures’ were different!
It would be instructive to look at what happened after Edison's little toy came into the 'market'. Comparisons were made between something newer and Edison's recording (measurement, again) and the public went after that elusive thing called 'better/higher fidelity'. This chase of the ephemeral continued until in the post-war era, when the world largely settled on 2-channel stereo as the ultimate in fidelity. 'Measurements', by now far more complex and more involved and so technical that you would need a degree in engineering to understand many, fuelled the forward march of stereo from then on.
And THEN we got lost in the forest of measurements, because we lost sight of the basic fact that measurement and understanding were the chicken and the egg!
Whether you are at a concert or merely walking the busy urban streets, or leisurely enjoying a walk in the wilderness, acoustical events impinge on your ears all the while. You are not merely trying to place each of the musicians from your front-row-centre vantage point. The sum-total of your acoustical experience builds and projects an image of "truth" in your mind. What are the acoustical characteristics/parameters that contribute to this? Do we understand them fully? Only when we can list out these parameters, we could think of identifying and classifying and perhaps recording and then later reproducing those parameters in an attempt at recreating the original "truth".
While considering acoustic events, it would be educative to look at the non-sighted navigating our urban cityscapes. I have often observed the average blind person using a "sensing stick" that produces echoes which tell him a lot about the environment. I personally know a gifted but visually challenged person who uses nothing except an occasional snap of his fingers while “navigating” at an astounding speed through a challenging "obstacle course" in the busy city centre, which would, at such speed, in all likelihood bring to heel a normally sighted person! I have seen him dodge an obstacle at his face level at the very last moment and ducking to negotiate a walkway. This should tell you that with training, the visual correlation that auditory signals can recreate in your mind is simply awesome.
When you begin to accept the complexity of what we are trying to understand with our simplistic measurements, then only you will admit the inadequacy of our tools and our primary understanding of acoustical events and the richness and complexity of their parameters.
What is needed at this juncture, IMHO, is a "brand new look" at what all characterize an acoustic event and how best to measure it, so that when we come to recording and then replaying it, we could conduct some more measurements and see what all we have lost in the process, and then perhaps learn how best to regain that --and along with that, the reality and the “truth”.
Listen and you will see what I mean, and for that you don’t need anything more exotic than what virtually all are fortunate to have--our ears!
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