The Cave and Church in Tomba Emmanuelle. Some Notes on the Ritual Use of Room Acoustics.
Petter Snekkestad
This article explores the acoustics of the Emanuel Vigeland Mausoleum through an associative history of reverberation. In particular, the sensory combination of reverberation and the fresco Vita in the darkened mausoleum echoes that of sound experiences in painted prehistoric caves and medieval churches. I also touch upon the notion of demarcation as a third ritual effect in these spaces.
Since its public opening in 1959, the mausoleum of noted artist Emanuel Vigeland (1875–1948) has attracted an increasing number of visitors. The interior of the dimly lit, rectangular and barrel-vaulted room is in its entirety covered by the fresco Vita, thematizing the miracle of human reproduction within a deeply Christian context (Jansen 1977). The monumental painting matured through different stages between 1927 to 1947, initiated only a year after the brick construction was erected in the residential area of Slemdal in Oslo. During that time, every window of the building was bricked shut in order to prevent natural light from entering into what would become the artist's mausoleum. The ashes of Emanuel Vigeland are contained in a hollowed, egg-shaped beach stone that rests in a niche over a conspicuously small door. Upon leaving the mausoleum one is forced to bow down to its creator.
Adding to the intriguing visual expression of Tomba Emmanuelle, a rich acoustic milieu reveals itself once the visitor has stepped onto the floor. Even careful footsteps resound and render quiet conversations unintelligible. It is tricky for the spectator not to let randomly emitted sound operate as a sort of accompaniment to the visual drama displayed in the fresco, as it defines the room to an unusual degree. This quality has struck a chord with experimental musicians recording or performing in the strongly reverberant space. One such performer notes that, despite the mausoleum's piercing reverberation, it houses a certain warmth and can stimulate the sensation of “being sucked into a vacuum” (Haltli 2003).
The interplay between wall art and darkened, reverberating rooms is one that humans have experienced and probably sustained for thousands of years. As we shall see, the Paleolithic painted caves of Central Europe as well as medieval churches in the Romanesque period bear witness to an appreciation for a sensory phenomenon that certainly support otherworldly experiences.[1] Can the religiously themed Tomba Emmanuelle be understood as a continuation of artistic expressions created in the sphere of rituals and multi-sensory imagery, serving to heighten spiritual experience? Unlike the modern listener, who is surrounded by reverberation in public buildings or through aural media, the pre-modern listener would find reverberation curious and possibly mysterious. Perhaps the extreme acoustics found in Tomba Emmanuelle manages to wake up our reverb-saturated ears, allowing us, in a sense, to experience anew the captivating sensation of sound waves traveling to and fro in a Stone Age cave or a medieval church.
It will serve us well to make a distinction between what is sound and noise and what can be termed reverberation or room acoustics. The former is a criterion for the latter, yet reverberation is created when sound waves are preserved or enclosed in a given space; in an open field they travel freely, but in an enclosure these waves meet obstacles and are reflected a number of times in different directions. The listener thus picks up reflected sounds from different angles of the room, some arriving from above, others from behind, and so forth. In more figurative terms it is like an oceanic wave that swiftly rises, tumbles over itself and then ebbs. Reverberation should not be confused with echo or other sound reflection phenomena one can readily experience in nature. A canyon can, for instance, enrich vocalizations and create reverberation-like effects as the sound travels and reflects off the rock surfaces. It is, however, only called reverberation when the sound space is enclosed, as in a room. The similarity between the two phenomena was articulated by the ambient act JUV who, in 1999, sampled reverberant noise in Tomba Emmanuelle to create music calling up associations with a dramatic, mountainous scenery: “[a juv is] that deep space between two mountain walls or inside a deep underground cave. It also brings to mind the echoing and reverberation of sound” (Juv 2010). A historical example of the appreciation of sound-enhancing elements in a landscape is found in Thingvellir on Iceland, the site of the medieval national legislative and judicial assembly, Althingi. Behind the Law Rock (Lögberg), on a sloping hill that forms a natural theatron, a cliff wall would allow for the speaker to be heard at a great distance (Byock 1993: 14–15). The effect would surely be impressive in a country dominated by highly sound-absorbing turf houses and with very few and modest medieval stone churches in which inhabitants might experience reverberant spaces.
Before Caves
To give some idea of the impact of room acoustics, imagining our Stone Age ancestors on the African savannah can serve as a point of departure. What was their sound milieu like, or, following R. Murray Schafer's (1993) term, how can we describe their soundscape? We can imagine that they were immersed by animal and insect sounds, communicating intensely during parts of the day and quieting down in others. One might hear heavy rainfalls and foraging companions shouting from a distance. At some point in our hominid evolution, the beating of drums or other percussion devices accompanied song. With the advent of stone tools arose the clinging sounds of stone knappers turning knolls into hand axes one stroke after the other. Although the richness of such a Pre-historic soundscape should not be downplayed, the myriad aural experiences in a distant past had fewer and more predictable sources than they do today. The savannah experience, so to speak, asks us to place in comparison an imagined experience of the Pre-historic acoustic repertoire to our modern soundscape of electronics and motors. It has been suggested that the post-industrial world has fundamentally changed our engagement with sound and that noise pollution “may be cutting humans off from their ancient sonic heritage, just as smoke and light pollution renders the once-impressive night sky almost meaningless to moderns” (Lubman 2007: 1819). The reverberant spaces we encounter in a number of buildings and hear reproduced in aural media offer a sensation that was unavailable to the ancient ear. In broad terms, hominids, including Homo sapiens as the latest off-shoot, have in their slow evolution over the span of some two million years spent their time in soundscapes devoid of room acoustics. In light of this timeline, the strange phenomenon that is reverberation is a fairly recent element of human aural perception.
This point is stressed by Barry Blesser and Ruth Salter, identifying a clear contrast between a hunter-gatherer soundscape and that of moderners, filled with reverberation (Blesser and Salter 2007). Sound reflections in outside environments, such as a forest, are modest; if reflected at all, sound returning to the ear from trees, rocks or other surfaces reach the ear within 0,02 seconds, which constitutes the straightforward, non-reverberant acoustic cues which the hunter-gatherer utilized to find and bring down prey. Our aural system is, therefore, to a large extent adapted to this sort of “dry” soundscape: it is the acoustics that has accompanied our modus operandi since bipedalism, or earlier, for that matter. In keeping with this, an evolutionary perspective regarding our senses can inform a modern perception of reverberation, illustrated by Blesser and Salter's question: “What does it mean to hear a concert hall with ears made for a forest?” (Blesser and Salter 2007: 340).
Arguably, the savannah scenario is key in understanding why room acoustics today – in the Tomba Emmanuelle or elsewhere – still tickle the ear. Yet, we have so far overlooked the fact that hominids did occupy caves and were to some extent, at least, exposed to reverberation. While it is difficult to form an idea of when and to what degree, tracing behavioral changes in hominids can provide hints. It is suggested that our latest ancestor – anticipating the emergence of the first Homo genus between 3–2,5 million years ago – the bipedal Australopithecus, relied heavily on trees for food and refuge. A need for the scavenging early humans to stay in the vicinity of forest-like environments continued to 1,8–1,7 million years ago, at least, when morphological evidence indicates a fully terrestrial lifestyle. The archaeological record in what is called the Acheulean Period – starting 1,7 million years ago and continuing until about 250 thousand years ago – suggests occupation on sites close to water with few extant caves. However, those cave sites that were perhaps inhabited have most likely not survived (Klein 2000: 19–23). Without going into detail, it should suffice to mention that cave occupation is evident in Africa and elsewhere after this period. So, our distant man-ape relatives evolved for millions of years in forest settings (Klein 2000: 18) that did not produce reverberation (the genetic divergence from chimpanzees starts between 8–5 million years ago), and it is unclear to which degree hominids in their infancy would venture into or dwell in caves. The question of whether these caves were deep and big enough to immerse the listener with reverberation is one which is beyond the scope of this article. In light of the above, I feel confident in my initial observation, namely that reverberation in evolutionary terms is a new phenomenon, which might partly explain its attraction. The psychoacoustic phenomena apparent in rooms, which I deal with below, might support such a claim.
Leaping forward in time to the Upper Paleolithic in Europe, between around 40 to 20 thousand years ago, fully developed humans were indeed inhabiting and conducting rituals in caves. Famous rock art caves are found in France at modern-day Chauvet and Clavoix. In addition to the skillful artistic depictions of fauna, scientists have suggested another ritualistic interest, namely the creation of sound effects that would in some cases accompany the drama displayed in the cave paintings. A pioneering study by Iegor Reznikoff and Michel Dauvois examined the correlation between acoustically favorable spots and the presence of rock art in three Paleolithic caves in Ariège in France (Reznikoff and Dauvois 1988: 238–246). They found that most of the “points of resonance,” and certainly all the most compelling ones, had paintings in their immediate vicinities. Conversely, sections of the caves with very little resonance response lacked paintings. Further developing their argument, they suggested that a certain point of resonance in Grotte du Portel was marked with red painted dots instead of the usual figurative image, as the rock surface was too small for a larger work. Such a marking would assist a small gathering of people to remember where their singing resonated strongly. Since this discovery, a number of studies on pre-historic acoustics have observed similar phenomena in other caves, reinforcing the argument of a connection between rock art, music and dance (e.g. Waller 2002: 11–22).[2]
So, I return to the proposition that caves have the ability to house and generate a sensory milieu that can benefit ritual acts. In comparing them with Romanesque churches as well as the Tomba Emmanuelle in the following section, I look at three ritual effects – namely demarcation, darkness and sound – and explore how they relate to each other.
Dangerous Space
An overarching aspect of collective rituals is their ability to attract attention (Durkheim 1995: 330–354). The highly structured and often carefully coordinated procedure in which the different acts arise, is somehow compelling for the participants or spectators. In an influential paper, anthropologist Roy Rappaport identified some of these attention-grabbing elements (Rappaport 1979: 173–217). We find a common, nearly universal pattern of seemingly meaningless acts that are often conducted within marked boundaries, with little or no contact between the divided areas. These acts serve no clear, pragmatic purpose, but the compulsive nature of the procedures call to mind the dangers that lie hidden if the acts are not carried out according to a given scheme.[3]
Through such an understanding, the Catholic ritual of carefully wiping the chalice and disc after communion becomes an attention-grabbing act due to its compulsive nature; something bad might happen if the procedure is not followed through.
In Romanesque stone churches from the Medieval Period, such acts were provided with a special sensory milieu. Firstly, the focal point of the liturgical service was the altar positioned in the choir. The choir was reserved for the clergy and clearly separated from the nave, which housed the onlooking and listening congregation. The chanting and highly structured ritual acts carried out close to the altar during mass follows Rappaport's scheme as described above; they were performed within the marked boundary of the chancel wall, which only a selected few were allowed to enter.
Secondly, in contrast to the tall and wide windows that arose due to technical advances of Gothic architecture, the preceding Romanesque style had narrowly shaped, and relatively few, windows. They allowed only limited portions of sunlight to enter the church. To some extent these churches were dark and gloomy, and the lighting was defined by oil lamps and candles. In this way, frescoes decorating interior walls were dimly lit and appeared in flashes from artificial light sources. The frescoes depicted, among others, the devil in various grotesque and animal forms, echoing a religious idea of the human soul as vulnerable to constant attacks from evil forces in the absence of God's protecting light. The sense of danger within a Romanesque church was expressed in both the structured rites performed in the choir (what would happen if they were not carried out?) and the threatening depictions on the dimly lit interior walls.[4] It has also been noted that sound, especially when accompanied by darkness, offers an ideal ritual marker in that it is all-encompassing and, reaches the participants with greater ease than visual stimuli (Jackson 1968: 295–296).
Alvin Lucier - Silver Streetcar for the Orchestra, performed by Håkon Stene and recorded in the Tomba Emmanuelle.
A third ritual effect can be caused by acoustics. Because reverberation time is defined by volume and reflecting surface materials, stone churches of a certain size significantly enhanced vocalizations such as plain song. Wooden churches did not exhibit this property, given the sound absorbing quality of their primary material. Hence, the avoidance of wood or drapery ensured a more reverberant space, and erecting stone vaults was discovered to be a particularly effective, albeit expensive, means to direct sound back down to the listener. Also, the wider and taller one could build, the longer sound could travel to and fro within the higher portions of the church without being absorbed by the garments or liturgical furniture of the assembly.
In my assertion that a reverberation time of, say, two seconds or more can best be understood as a ritual effect, I would like to point out that stone buildings in medieval Scandinavia belonged primarily to the ecclesiastical or royal sphere. Profane stone architecture erected by the aristocracy was relatively uncommon and could not, in any case, compete with the symbolic complexity of monumental, reverberant churches. Therefore, common people were exposed to reverberation only within the sacred milieu of a local parish church or, for instance, in an impressive cathedral along a pilgrimage route. One might argue that the Catholic Church had a monopoly on the ritual use of reverberation, made possible by its economic and spiritual power to erect, or inspire lay Christians to erect, grand stone structures. With regards to hominid evolution and the lack of adaptiveness to room acoustics as discussed above (“What does it mean to hear a concert hall with ears made for a forest?”), another layer of wonderment ought to be added within a medieval sacred context: What did it mean to hear plain song reverberating in a space that embodied Christ? It is a question that leads me to ask how we today, as disenchanted and secular listeners, train our ears to the acoustics of Tomba Emmanuelle.
Cave + Church + Tomb
It appears that the Catholic Church made possible at least three ritual effects in the Romanesque stone churches of Scandinavia. Demarcation of the area in which ritual activity took place caught attention, while narrow and few windows allowed for an interplay between darkness, light, and figurative art. Lastly, reverberation interwove the ritual space and created an unusual auditory milieu. In singling out these three elements, which in no way encapsulates or sums up the ingredients for a spiritual experience of the period, a certain ritual leitmotif travels through this foggy prehistory, emerges in myrrhy basilicas, and ends up in a modern mausoleum in Oslo. The combination of demarcation, darkness, visual art, and reverberation can be understood as a liturgical sensory package that comes together nicely, or, moreover, is dependent of each other for full effect. In Tomba Emmanuelle, demarcation is the least articulated feature. Nevertheless, demarcation serves as a vantage point in discussing how these features manifest themselves at different times and under different circumstances.
As noted above, the Romanesque church had a clearly defined boundary between the choir and nave, separating the celebrant's area of worship between the alter and the congregation. In a sense, the smaller and narrower choir focused the orderly and compulsive manner of worship into a comprised and meaningful space. Archaeologist David Lewis-Williams' interpretation of communal rites in European Paleolithic caves touches upon this type of ordered activity. Here, an assembly was gathered in chambers of the cave where rites were performed and rock art displayed – perhaps with accompanied animal sound effects – in the flickering light of torches and oil lamps. However, a selected few took it upon themselves to enter the deeper, narrower passages of the cave in a spiritual vision quest (Lewis-Williams 2002: 220–236). The exclusivity of the quest, which is a common thread in shamanism, can be seen to be reflected in the social and spatial distinctions drawn up between officiant and spectators in church liturgy.
Tomba Emmanuelle is not a place of religious worship and obviously not spatially ordered for such a purpose. Yet, Vigeland initially had ambitions of erecting his own monumental church, and it is not an exaggeration to say that he intended the tomb to house a worship of his art in one way or another (Furnes 2005: 183). In order to enter Tomba Emmanuelle, one must pass through a tiny atrium, which serves as a defined separation between the nearly holy and the holy, so to speak. Daylight fills the atrium, and one prepares to enter the dark tomb through a shallow doorway. Apart from the fact that the frescoed interior walls are fenced off, an efficient demarcation is manifested in the corporeal act of passing through the shallow doorway: one bows down to pass under the upper frame, rising gently while closing the door behind oneself. As the handle locks into place, a booming thump resounds through the air, bringing attention immediately to the auditory and, on a subconscious level, to the physical qualities of the room. Simultaneously, when gently rising to an erect position, the visitor catches a first glimpse of the mural paintings in an almost pitch-dark space, eyes not yet attuned to the sudden change of ambience.
There is a grandiosity to this arrangement which demands a certain reverence from the attendee, much like stepping onto the tiled floor of a cathedral and noticing how the reverberating clacks underlines its sacredness: God is present, and He is all ears. This auditory grandeur works in secular settings as well. Just think of how those same clacks resounding in a high-rise’s marble-dressed bank reception area sends a clear message of financial and institutional power.
Although the drama of liturgically separating officiant and spectator is lacking in Tomba Emmanuelle, the auditory separation between two modes of human observance is present. Just as the visitor is jolted into the mystical theme of Vita with the bang of the door, the Eucharistic moment of transformation of Christ's body into wine and bread was marked by the tolling of bells in medieval churches. If we extend the attention-grabbing physical demarcation of a building to an auditory one, Tomba Emmanuelle does in my opinion entertain a ritualistic trick in the demarcation between atrium and tomb. The secular twist, so to speak, is that the visitor is also a celebrant, not merely a spectator.
A Transcendent Room
Carefully illuminated spaces offer special sensory qualities. The darkness preserves hidden features of a room and launches us into wonderment. The inner boundaries of Tomba Emmanuelle are not immediately graspable for the visitor, and neither are the extent or nature of the frieze covering it. Nevertheless, a general idea of the mausoleum's outline and volume can be formed not long after exposure. Given that we at first glance cannot fully see its size, can we actually hear it?
We have arrived here at the locus of my investigation. This is to say, although demarcation plays a part in the sensory complexity of Tomba Emmanuelle, it is the confusing sensory maelstrom of reverberation, frescoes, and darkness that taps into certain abilities, or rather disabilities, of our minds. As already noted, our ears were not made for caves, churches, or tombs, but for forests. Unlike vision, in which cognitive interpretation corresponds well with the physical reality interpreted, our ears are not finely tuned to precisely analyze the physical extents or qualities of a reverberant space. So, the question “can we hear the size of Tomba Emmanuelle?” must be answered with both a “yes” and a “no.” Our auditory system simultaneously reads and misreads reverberant surroundings. This deserves some further commentary.
To make sense of this world, we make inferences concerning the nature of our surroundings. Vital sensory information is often lacking, and our brain performs guesswork on the basis of past experiences. For instance, we recognize a straight rod even when only the two ends are visible to us. Because they are aligned and bear resemblance to each other, our brain couples the two ends, and we infer that it actually is one and the same object. This and other similar cognitive exercises are performed effortlessly and without further reflection, but they demand a certain leap of faith and do not necessarily correspond with the physical reality observed. As the veil is removed, we might realize that the perceived rod is in fact two separate pieces. In a similar way, the human auditory system tries to map out our surroundings from reverberant sonic events. Whether in a cave, church or mausoleum, our ears have the facility to pick up information about a space as sound waves travel back and forth; the auditory system neatly measures the arrival times of sound reflections at the two ears in relation to the sound source. In this way, the acoustics of Tomba Emmanuelle provides the listener with information about its physical properties. Given that, upon entering, the mausoleum was pitch-dark, sound would be the sole cue informing a visitor concerning size and shape. Albeit confusing, the myriad reflections that constitute a reverberating space provide hints to the volume and surface material of a more or less unseeable enclosure (Shepard 1999: 21–36).
However, this capability has its limits. Analyzing reverberation also spawns certain sound illusions leading less to accurate inference and more to a misunderstanding of room size. The reverberation of Tomba Emmanuelle gives the impression of invisible sound sources beyond and outside its actual perimeters. Playing a flute in the middle of the tomb creates an illusion of multiple flutes at different points both inside and outside the frescoed walls. The effect can be likened to how a Spiegelsaal gives the illusion of undefined size; new rooms are created behind and beyond the actual inhabited space (Shepard 1999: 28). As the acoustician Jürgen Meyer noted with regard to sound milieus in large churches, the visually enclosed space is paradoxically the very premise for the auditory endless one (Meyer 2002: 89). It is as if immediate physical reality is somehow suspended.
In the case of Tomba Emmanuelle, its architecture and interior order does indeed invite this acoustical phenomenon. It has been described as an “exceptionally reverberant hall,” with a reverberation time of around 8 seconds for mid-frequencies, when occupied (Buen 2008: 108). Unoccupied, the room resounds with an extraordinary 14 seconds in the low- and mid-frequencies. The richness of the mausoleum's acoustics seems disproportionate to its size, which might explain some of its intrigue. It is not surprising to find reverberation times exceeding 10 seconds in monumental medieval cathedrals, but it is highly unusual for a hall of more modest proportions. The long reverberation time must be mainly attributable to the sound reflecting quality of the 800-square-meter frieze Vita, whose paint on concrete and plaster absorbs very little sound energy. The waxed, tiled floor and the general lack of sound absorbing materials contribute to this. In addition, interior outline and proportion craft the acoustics in a defining way. The rectangular, high-rise form of the mausoleum, also called a “shoe-box,” is a principle acoustical design and common amongst concert halls for classical music.[5] The simple church-like plan creates a sound milieu of early reflections from the side walls and late, often bass-like (given their physically longer sound waves), sound reflections between the two end walls. Unlike a square room, which resonates within a narrow frequency spectrum, the “shoe box” ensures that a wider frequency spectrum can resonate, due to the non-corresponding room dimensions. In turn, room resonance enhances reverberation time. The height, which exceeds the width of the end walls, enriches this spectrum of frequencies and allows for reflections to be slung to and fro along the upper parts of the hall before eventually descending to listeners on the ground. Also, the barrel-vaulted ceiling contributes to the acoustic complexity, as it both scatters and, more importantly, focuses sound reflections toward given points (Baumann and Niederstätter 2008: 54–59). The vault both visually and acoustically echoes Romanesque architecture. In medieval Romanesque churches the tunnel vault was perhaps preferred partly because of its ability to enhance plain song in churches.[6]
Recognizing the entrancing auditory prisms made possible by Tomba Emmanuelle, visual art and acoustics engage in a curious companionship. Between the listener and the “endless” hall – in other words, the illusionary space beyond the hall's physical boundaries – Vita seems to mark off the zone between us and the other-worldly. Its people are not settled in recognizable landscapes, but float in the foreground of a black void that might be regarded as an endless space. The darkness serves to soften or bridge the gap between the actual inhabited space of the opaque tomb and the one that can be heard beyond it.
I dare say that the acoustics brings forth a sensation of transcendence in the Vita. Its limitless and myriad quality mirrors a core element of the Christian faith, in which context the frieze was painted. Just as God exists apart from us, that is, beyond what humans are capable of grasping, the acoustics of Tomba Emmanuelle points to a sphere that lies apart from and beyond its physical extent. We might imagine that it hints at, or perhaps simulates, what this unknowable divine sphere could be like. Moreover, this auditory effect, this acoustic simulation of transcendence, can be heard not only in the mausoleum – although articulated here to an unusual degree – but also in the frescoed medieval churches and painted prehistoric caves, where reverberation and darkness propelled a spiritual and unseeable world beyond their surrounding walls. For the pre-modern, porous self in an enchanted world, these effects would take on a meaning that we today may find hard to grasp fully.
Thus, if we are to believe the claim that our modern soundscapes, with their motors and electronic devices, have cut us off from the observant hearing of the old, the significant acoustics of Tomba Emmanuelle arouse our sedated ears and allow us to re-experience the naive wonderment that once filled caves and early churches.
Diagrammatic representation of ritual use of caves in the Upper Palaeolithic. From (Lewis-Williams 2002: 267).
Cognitive misinterpretation of reverberation. Virtual sound sources are heard beyond the room. From (Shepard 1999: 28).
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