The Soundscape: Our Sonic Environment And The Tuning Of The World

by R. Murray Schafer

  Early sound engineers sought to carry over special acoustic properties like these into the ziggurats of Babylon and the cathedrals and crypts of Christendom. Echo and reverberation accordingly cany a strong religious symbolism. But echo and reverberation do not imply the same type of enclosure, for while reverberation implies an enormous single room, echo (in which reflection is distinguishable as a repetition or partial repetition of the original sound) suggests the bouncing of sound off innumerable distant surfaces. It is thus the condition of the many-chambered palace and of the labyrinth.

  But echo suggests a still deeper mystery. Acousticians will explain that the reflection of a sound off a distant surface is simply a case of the original wave bouncing back, the angles of incidence and reflection being equal. In order to understand this effect one may project a mirror image of the original sound deep behind the surface, at exactly the same distance and angle from the surface as the original. In other words, every reflection implies a doubling of the sound by its own ghost, hidden on the other side of the reflecting surface. This is the world of alter-egos, following and pacing the real world an instant later, mocking its follies. Thus, a far more potent image than Narcissus reflected in the water is that of Narcissus’s alter-ego mocking his voice from unseen places behind the rocks. Lucretius, whose philosophy blends science and poetry so skillfully, catches something of this magic quality in his description of the echo:

  One voice is dispersed suddenly into many voices. … I have even seen places to give back six or seven cries when you uttered one: so did hill to hill themselves buffet back the words and repeat the reverberation. Such places the neighbours imagine to be haunted by goat-foot satyrs and nymphs … they tell how the farmers’ men all over the countryside listen, while Pan shaking the pine leaves that cover his half-human head often runs over the open reeds with curved lip, that the panpipes may never slacken in their Hood of woodland music. … Therefore the whole place is filled with voices, the place all around hidden away from sight boils and stirs with sound.

  Reverberation and echo give the illusion of permanence to sounds and also the impression of acoustic authority. Thus they convert the sequential tones of melody into the simultaneously heard chords of harmony. In open Greek amphitheaters where reverberation was of negligible significance ("never more than a few tenths of a second") harmony was also absent in the musical system. The fact that the theory of harmony was slow to develop in the West was probably due to the way in which Pope Gregory and the medieval theoreticians took over Greek musical theory. Here we have an example of a cultural inheritance inhibiting a natural development, that is, the polyphonic potential of the enclosed forms of Romanesque and Gothic cathedrals. The reverberation of the Gothic church (up to 6–8 seconds) also slowed down speech, turning it into monumental rhetoric. The introduction of loudspeakers into such churches, as has recently happened, does not prove the acoustic deficiency of the churches but rather that listening patience has been abbreviated.

  The size and shape of interior space will always control the tempo of activities within it. Again this may be illustrated by reference to music. The modulation speed of Gothic or Renaissance church music is slow; that of the nineteenth and twentieth centuries is much faster because it has been created for smaller rooms or broadcasting studios. This development reached its climax in the highly concentrated, information-packed music of the twelve-tone composers. The contemporary office building, which also consists of small, dry spaces, is similarly suited to the frenzy of modern business, and thus contrasts vividly with the slow tempo of the Mass or any ritual intended for cave or crypt. Now again, the attenuated effects of the newest music seem to suggest a contemporary desire to slow down living pace, just as the music of Stravinsky and Webern had foreshadowed modern business practice.

  The Architect as Acoustic Engineer in Antiquity in a moment I will have some harsh things to say about modern architects’ abilities as acoustic designers. But to prepare the case against them it is ecessary to consider them in comparison with their ancient colleagues. Architects of the past knew a great deal about the effects of sound and worked with them positively, while their modern descendants know little about the effects of sound and are thus reduced to contending with them negatively.

  The early builders built with ear as well as eye. The exceptional acoustics of the Greek amphitheaters, of which the Asclepius theater at Epidaurus is perhaps the best example, do not prove that acoustics had been totally mastered in ancient Greece, but they do show that a general philosophy of building existed in which acoustic considerations helped determine the form and siting of the structure. In the empty amphitheater at Epidaurus the sound of a pin dropping can be heard distinctly in each of the 14,000 seats—an assertion I have put to the test. That Greek actors were frequently depicted wearing masks with megaphones attached to their mouthpieces does not show that ancient theater acoustics were a failure but merely that Greek theater audiences were probably unruly.

  The most beautiful building I have ever experienced is the Shah Abbas Mosque in Isfahan (completed AD. 1640), sumptuously elegant in gold and azure tile, with its famous sevenfold echo under the main cupola. One hears this echo seven times perfectly when standing directly under the apex of the cupola; standing a foot to either side one hears nothing. Experiencing this remarkable event one cannot help thinking that the echo was no mere byproduct of visual symmetry but was intentionally engineered by designers who knew perfectly well what they were doing and perhaps even used the echo principle in determining the parabolic features of their cupolas.

  Something similar apparently exists in the Temple of the Ruler of the Universe in Peking. The actual temple is a circular building, surrounded by a circular wall, inside which are two rectangular buildings, probably indicating the place of the earth within the universe. If a person stands in the center of the site and claps, a series of rapid echoes is heard, caused by reflections from the outer wall. But by moving slightly off-center the echoes will change completely, because only every second reflection will return to the point of origin. In other places near the center, the acoustical conditions are even more complicated, and the echoes will change with even the slightest shift in the placement of the sound-producer. Within this structure it is also possible for persons to converse naturally at great distance when standing just inside the circular wall, for this flat hard-surfaced wall reflects sound around its inner surface with a minimum of transmission loss.

  Unfortunately, we have no accounts of how or why acoustic specialties were incorporated into ancient buildings such as these, but since all ancient cultures were strongly auditory, they were quite probably conceived deliberately to express divine mysteries, and at any rate they were certainly not the unpredictable consequences of blueprint accidents. W. C. Sabine, the best architectural acoustician of modern times, studied the"whispering galleries” of some newer buildings: the Dome of St. Paul’s Cathedral in London, Statuary Hall in the Capitol at Washington, the vases in the Salle des Cariatides in the Louvre in Paris, St. John Lateran in Rome and the Cathedral of Girgenti. Sabine’s conclusion: “It is probable that all existing whispering galleries, it is certain that the six more famous ones, are accidents; it is equally certain that all could have been predetermined without difficulty, and like most accidents would have been improved upon.” But these were expressions of a time which was exchanging its ears for its eyes, of a time when the engineering drawing was becoming the prerequisite of architectural thought. This was not so in the Asclepius Theater, in the Shah Abbas Mosque or in the Temple of the Ruler of the Universe. They cannot be “improved upon,” for they resulted from the synchronous interaction of the eye and the ear.

  Among the classical papers on architecture none is more voluminous or respected than the ten books of De Architectura by the Roman Vitruvius, which date from about 27 B.C. Book V adequately demonstrates the writer’s familiarity with the importance of acoustics, especially in the building of theaters, where, following an
extensive exposition of the principles of the Greek science, he discusses the employment of sounding vases in theaters to enhance sound production. Vitruvius writes:

  Hence in accordance with these enquiries, bronze vases are to be made in mathematical ratios corresponding with the size of the theatre. They are to be so made that, when they are touched, they can make a sound from one to another of a fourth, a fifth and so on to the second octave. Then compartments are made among the seats of the theatre, and the vases are to be so placed there that they do not touch the wall, and have an empty space around them and above. They are to be placed upside down. On the side looking towards the stage, they are to have wedges put under them not less than half a foot high. Against these cavities openings are to be left in the faces of the lower steps wo feet long and half a foot high. …

  Thus by this calculation the voice, spreading from the stage as from the centre and striking by its contact the hollows of the several vases, will arouse an increased clearness of sound, and, by the concord, a consonance harmonising with itself.

  That these techniques were not special to Vitruvius, we know from the author’s own assertion: “Someone will say, perhaps, that many theatres are built every year at Rome without taking any account of these matters. He will be mistaken in this.”

  These sounding vases were what we now call Helmholtz resonators, and whether or not they originated in Rome, they appear to have been widely used throughout Europe and Asia in the following centuries. They were used in the Shah Abbas Mosque of Isfahan and have been found built into the walls in a number of old Scandinavian, Russian and French churches. In the case of the European churches, the principle appears not o have been completely understood, for the sounding vases do not exist there in sufficient number to produce any noticeable acoustic effect. But a recent discovery of a large quantity of sounding vases (fifty-seven in all) in the small fifteenth-century abbey church at Pleterje, between Ljubljana and Zagreb, shows that the tradition was accurately understood by the Yugoslavian builders, for the double resonance system employed in this case resulted in a high absorption over a broad frequency band from 80 to 250 hertz, an area in which the reverberation time in brick chapels is normally much too long.

  From Positive to Negative Acoustic Design Architecture, like sculpture, is at the frontier between the spaces or sight and sound. Around and inside a building there are certain places that function as both visual and acoustic action points. Such points are the foci of parabolas and ellipses, or the intersecting corners of planes; and it is from here that the voice of the orator and musician will be heard to best advantage. It is here also that the metaphorical voices of sculptured figures will find their true position, not on the metope or tympanum or porch.

  Old buildings were thus acoustic as well as visual spectacles. Into the handsome spaces of the well-designed building, orators and musicians were attracted to create their strongest works; there they gained a reinforcement denied them in most natural settings. But when such buildings ceased to be the acoustic epicenters of the community and became merely functional spaces for silent labor, architecture ceased to be the art of positive acoustic design.

  In a quiet world, building acoustics flourished as an art of sonic invention. In a noisy world it becomes merely the skill of muting internal shuffles and isolating incursions from the turbulent environment beyond. Thus the great high-rise towers of the world stand on tiptoes, looking out across the fires of the city. Bellevue—mats mauvais son.

  The Modern Architect as Acoustic Designer One day I was discussing matters of mutual interest with a group of architecture students. Drawing a picture of a possible future city on the blackboard I asked them what the salient features of this environment appeared to be. There were seven helicopters in the sky of my drawing, yet no student found this particularly salient. I (exasperatedly): “Have you ever heard seven helicopters?”

  The modern architect is designing for the deaf.

  His ears are stuffed with bacon.

  Until they can be unplugged with ear cleaning exercises, modern architecture may be expected to continue its same rotten course. The study of sound enters the modern architecture school only as sound reduction, isolation and absorption.

  Listen to the sounds a building makes when no one is in it. It breathes with a life of its own. Floors creak, timber snaps, radiators crack, furnaces groan. But although buildings of the past made characteristic sounds, they cannot compete with modern buildings for the strength and persistence of sound emitted. Modern ventilation, lighting, elevators and heating systems create strong internal sounds; and fans and exhaust systems disgorge staggering amounts of noise into the streets and onto the sidewalks around the buildings themselves.

  Architects and acoustical engineers have often conspired to make modern buildings noisier. It is a well-known practice today to add Moozak or white noise (its proponents prefer to call it “white sound” or “acoustic perfume") to mask mechanical vibrations, footsteps and human speech. The following thoughts from a recent textbook are typical of the present message being pushed at the graduates and flunctuates of the architectural profession.

  Contemporary environmental control can create a complex artificial environment in buildings that will meet all the physical, physiological, and psychological requirements of the occupants. This artificially created synthetic environment is in many respects superior to the natural one. No exterior atmosphere is comparable to an air-conditioned and humidity-controlled room. Lighting fixtures presently available will not only simulate daylight but will create an improved (shadowless) luminous environment indispensable for certain activities.

  The author of these comments is Leslie L. Doelle and the book they came from appeared in 1972. Concerning noise suppression Mr. Doelle has this to say:

  On the other hand, if the sound is undesirable (noise from a neighbor’s television set or traffic noise), unfavorable conditions must be provided for the production, transmission, and reception of the disturbance. Measures must be taken to suppress the intensity of the noise at the source; an attempt must be made to move the noise source as far as possible from the receiver. The effectiveness of the transmission path must be reduced as much as possible, probably by the use of barriers which are adequately sound or vibration-proof, and the receiver must be protected or made tolerant to the disturbance by using noise or background music. All these measures belong to the realm of noise control. …

  The phenomenon of masking is properly exploited in environmental noise control. If a masking noise is uninterrupted and not too loud, and if it has no information content, it will become an acceptable background noise and will suppress other objectionable intruding noises, making them sound psychologically quieter. Ventilating and air-conditioning noises, the noise created by uninterrupted traffic flow of a highway, or the sound of a water fountain are good masking-noise sources.

  So much for the memorial drool of Leslie Doelle.

  There may indeed be times when masking techniques can be useful in soundscape design but they will never succeed in rescuing the botched architecture of the present. No amount of perfumery can cover up a stinking job.

  You are being too severe, the profession insists. In the acoustic design of concert halls and auditoriums, architects and acoustical engineers have brought their work down to a fine science. The fact is that the inventor of room acoustics, Wallace Clement Sabine, still remains, after seventy-five years of this so-called science, its only real luminary. Sabine’s Symphony Hall in Boston is still considered probably the finest hall in North America, and it was opened in 1900. Sabine aimed to reproduce the acoustics of the Leipzig Gewandhaus, which has a reverberation time, when empty, of 2.30 seconds. Though the seating capacity of the Boston hall was to be about 70 percent larger than the Leipzig auditorium, he managed to come remarkably close with a reverberation time of 2.31 seconds (empty).

  The problem with most modern halls is that they are too large. Here, as in all other aspects of modern lif
e, quantity considerations have forced quality sacrifices. A comparison of some of Europe’s best halls (created before the so-called science of acoustics took over) with some pregnant modern structures reveals this clearly enough.

  PLACE DATE BUILT TOTAL AREA IN SQUARE METERS

  Vienna: Grosser Musikvereinsaal 1870 1115

  Leipzig: Neues Gewandhaus 1886 1020

  Amsterdam: Concertgebouw 1887 1285

  New York: Carnegie Hall 1891 1985

  Boston: Symphony Hall 1900 1550

  Chicago: Orchestra Hall 1905 1855

  Tangle wood: Music Shed 1938 3065

  Buffalo: Kleinhans Music Hall 1940 2160

  London: Royal Festival Hall 1951 2145

  Vancouver: Queen Elizabeth Theatre 1959 1975

  One of the most spectacular buildings of modern architecture is the Sydney Opera House. The sight of its huge cream-colored butterfly wings, seen from the little, elderly ferries which ply the harbor, is indeed unforgettable, even though the location of the building is convenient rather than inspirational, for the vulgarity of the Sydney skyline behind it and especially the great inelegant bridge at its side, do it no good.

  Shortly before it opened in 1973,1 was taken on a tour of the Opera House by its sound consultant. I was pleased to note the incorporation of large natural Helmholtz resonators in the walls of the concert hall—functioning more or less exactly as Vitruvius described them two millennia ago—the only hall I know to boast the revival of this technique. In the lobbies, however, I noted the innumerable little speakers which betrayed the inevitable Mooze installation. “The public seems to want it,” my guide said feebly.