Chavín de Huántar is an archaeological site in the Peruvian Andes, where a major temple complex has existed for several thousand years. The site has a number of temples and ceremonial plazas, and is honeycombed with corridors, shafts, and drains built of stone block. It is currently believed that construction of the major ceremonial buildings began around 900 BCE, and ended around 600 BCE. The non-ceremonial archaeological sites surrounding the main temple complex show signs of an emerging social stratification during the period that Chavín was active as a ceremonial center.

Professor John Rick of Stanford University (who was my undergraduate adviser in Anthropology) has been conducting research at Chavín since 1995. Rick has recently published several papers that put forth a provocative theory: that the structures at Chavín were used in rituals where the dominant “priests” (or whatever class was in power) relied on sensory manipulation, in combination with hallucinogenic drugs, to reinforce the perception that they had supernatural authority. This perceived communication with the gods, or godlike nature of the dominant class, would serve to justify and perpetuate the social stratification that was emerging at Chavín.

In his 2005 paper, The Evolution of Authority and Power at Chavín de Huántar, Peru, Professor Rick lists the evidence that the structures at Chavín were used as part of a “Tradition-Based Convincing System.” A brief summary of his arguments from this paper and other papers follows (all images are sourced from this paper).

The stone passages known as galleries have very unique sonic characteristics, where sounds are difficult to localize. Within these galleries, Rick recently excavated a number of decorated trumpets, carved from the Strombus conch:

The Strombus conch shells have been used as musical instruments in Peru for several thousand years, as depicted in this artwork drawn from a cornice at Chavín:

Along the Peruvian coast, conch were used as food (and still are to this day, and taste delicious in soup, especially if the soup has a spicy coconut-onion base). However, Chavín is a fair distance from the coast, so the presence of ornately carved conch shells there points to a society that had extensive trade associated with ceremonial practices.

The galleries are marked by ducts known as ventilation shafts and drainage canals, but these ducts seem poorly designed for this proposed usage. In 1976, Luis Lumbreras published a paper, Acerca de la función del sistema hidráulico de Chavín, where he argues that the “drainage canals” were used primarily for sonic purposes. When water was pored into these canals, the galleries below were filled with a roaring sound.

There is a fair amount of evidence at Chavín for the use of psychoactive drugs, in particular the San Pedro cactus, or Echinopsis pachanoi. This tall columnar cactus is native to the Andes, and there is evidence that San Pedro been used in rituals in the region for over two thousand years. At Chavín, the distinctive ribbed shape of the San Pedro cactus can be seen in carved figures:

Chavín also has a number of carvings of semi-humanoid, semi-animal figures. Such figures may represent the shamanistic transformation of a person into an animal spirit. Rick argues that such figures represent an “exceptionally graphic depiction of the drug effects and transitions.”

A summary of how Professor Rick thinks the ritual may have proceeded, from a recent profile of his work:

The ritual would have begun, most likely, by ingesting a hallucinogenic powder or a liquid extracted from the San Pedro cactus. As the Chavín subjects walked through the dark, cramped halls, the sound of Strombus trumpets echoed around them from some unseen source. Water roared through canals beneath their feet (or, strangely, overhead), producing a heavy percussion amplified by the drugs. Mirrors placed in ventilation ducts to reflect the sun poured brilliant shafts of light into the subterranean hallways, only to be “turned off,” thrusting the occupant into blackness as dark as obsidian. By the time the subjects emerged from the chambers, staggering and stunned, their perspective had been altered forever. The unmistakable impression: somebody powerful was in charge.

The descriptions of the sonic qualities of Chavín are fascinating; however, it is hard to quantify such qualities from words alone. Clearly, the galleries have unusual reverb characteristics. In the next post, I will discuss a recent expedition to Chavín, where Professor Rick was joined by a number of prominent figures in audio DSP and computer music in order to capture and analyze the reverberant qualities of the galleries.