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Room Acoustics Re-visited (2008)

Single Screen Projection


11 mins 5 secs 

Introduction to the Sonic Research Institute 

Depts of Musicology, Conservation and Reconstruction.


Sometime in the early 70's as far as we can tell , Dr. K. Heinrich's research began to gain critical attention. It was, to be specific, her findings that acoustics might be amenable to certain isolating treatments that heralded a new era. 


It would appear that the enthusiasm with which her proposals were greeted was a product of an increasing concern with what was considered "noise pollution". 


Meanwhile in the popularisation of some of her methods, Dr. Heinrich's warning that, "sensational failure may occur in the field from time to time", was forgotten in the excitement provoked by her experiments in time space and sound waves. Or perhaps simply misunderstood.


As mentioned, Dr. Heinrich developed a technique to remove what she termed 'acoustical defects' from a given sound field. The doctor herself argued with a growing sense of alarm that the methods employed to determine what might usefully be classified as noise, should be as sensitive as possible. However, it has been argued that the chink in her methods which allowed an opening of the floodgates, was her assertion that in the final analysis, the listener is always right. 


In the subsequent period of often heated debate and general misunderstandings and confusion as to where the line lay between sound and noise, it was agreed at governmental level that all sound above a certain decibel level, which was not clearly and purposefully organised, fell within what was becoming an ever-expanding field of noise and should be removed from the audible register. 


Despite Dr. Heinrich's insistence that the sound field in a real physical space is so complicated that it is not open to exact mathematical treatment, the inherent dangers and possible risks were considered worth taking.


There then followed a period of what was termed 'vibrational sweeping': a wide- spread radical condensing and simplification of sound fields with the purpose of controlling or eliminating random elements.* 



 *This process is now generally regarded as a destructive technique on two counts:

a) the treated material cannot be retrieved once it has been 'condensed' or reconstituted without considerable time and patience. At times the correct sonic results must simply be estimated. 

b) much of the original recording materials took the form of magnetic tape and were adversely affected  if they were anywhere within the vicinity of the sweeping blasts.

Where these random sound elements do still crop up, the impression is of sonic weeds or erratic ornaments in a vast perfectly manicured (and muted) aural terrace. Noting her own melancholic fascination in later years with these acoustic outcroppings, Dr. Heinrich suggested that while this 'lack of uniformity' (which is its main characteristic), is responsible for many of its difficulties, it also accounts for the continuous power of attraction these random sound elements exert on a growing number of acousticians.



At the time of writing, one must now contend with the widespread blanket of oppressive silence which followed in the wake of an almost total elimination of random sounds. 


While the young researcher may lament the sparse information remaining from the printed sound files of the time, it should be borne in mind that what survives is due to a process performed in extremis, when a small number of independent practitioners were beginning to sense the potentially disastrous impact of vib-sweeping on the sonic landscape. The difficulty of reconstruction is compounded by what has been perceived as an apparent reluctance in literature and scores of the time to adequately account for these sounds. This must be understood in the context of a world view that experienced most unstructured sound as noise. 


Given the above, while the work of retrieval and reconstitution is certainly one of the most time-consuming fields, it is also one of the most creatively challenging research areas of our generation.  



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