3. CONTENT OF SURFACE NOISE

Wouldn't it be NICE if surface noise were just surface noise - a mere interruption of listening pleasure, devoid of any informational significance? Certainly this viewpoint has been the basis for much experiment aimed at reduction of noise without consideration of the wealth of valuable peripheral information contained within it: minute detail which reveals the taking of a breath, the movement of a finger on a guitar string or the manner in which a brass player breaks from one harmonic to another or that in which a reed player uses his tongue; upper frequency reverberations which tell of environment ... the size and shape of a room... which affect the manner in which a musician plays. Even more important are the upper harmonics which identify not only instruments of differing principle but also those of similar principle (such as trumpet and cornet)... very often, such very individual information will allow separation of a "section" of trumpets from a numerically indeterminate group into a group of separately recognisable voices. Thus it is important to preserve and make use of this information - and to take a closer look at how the ear hears surface noise and what it can do with it.

Surface noise not only contains an indispensable abundance of peripheral information but can be shown to provide another extremely valuable asset in the form of an aural "anchor". A constant undercurrent of noise will readily be converted by the ear into an ignored continuity-base for the listening process. The interruption of such constant undercurrent - whether by click or silence - will immediately restore the noise element to perception. A recent American CD devoted to the Boswell Sisters offers an example in which the engineer, believing that a pause in the performance contained no information, on several occasions briefly removed ALL sound - so destroying the continuity of the otherwise constant undercurrent - and requiring aural readjustment on each occasion. Had the engineer left just half of the apparently useless noise, the result would have been the same. It was important that he maintain all the continuity merely to assure the ease of listening which he intended. Automatic Level Control devices will similarly destroy the "anchor" by "pumping".

Assuming that it has been possible to smooth the aforementioned undercurrent, more can be achieved by positioning the noise by colouration. Just as a visual artist will establish or enhance perspectives and distances by colouration (primary colours in foreground being reduced toward blue in middle distance and purple in far distance), a sound engineer can apply a very similar system so that, of choice, a curtain of in eradicable noise can be transferred from a position in front of the programme to one preferably immediately behind the principal sounds or, in some cases, even futher back where its distraction can be minimized. There will be occasions when a shift of such position my seem appropriate during a performance... but, if in doubt, leave well alone: almost any such alteration my be perceived - in which event it will be well to remember that "if you can hear what has been done, then it has been overdone".