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Archaeoacoustics
eled sound source. If archaeological sound must be recon- structed to be observed, is archaeoacoustics, therefore, a purely interpretative practice? Reconstruction and interpre- tation, although related, are not the same. The interpretative aspects of archaeoacoustical reconstruction depend on the way in which sound is produced as well as the choices of source and receiver locations that reenact human perspec- tives for contextual sound transmission.
Archaeoacoustical measurements made by exciting spatial or instrumental acoustics using an impulse (approximating a Dirac function) or a robust method for generating a spatial impulse response, such as the repeated exponential sinusoi- dal sweep technique developed and refined by Farina (2007), reveal archaeological acoustical features rather than recon- struct specific sounds. The impulse response can be thought of as a “spatial identifier,” a composite acoustical feature set that reveals how the physical constituents of a space or instrument affect sound propagation. In contrast, human- performed acoustical test sounds, via artifact or replica in- struments, are more interpretative, although the choice of particular instruments and the ways of playing them can be aligned with archaeological evidence. Reconstructive mod- eling and auralization of spatial and architectural acoustics likewise involve choosing sound sources and many other in- terpretative factors related to content, sound-making phys- ics, and listener perspectives. Reconstructive interpretation, when informed by archaeological evidence, emphasizes the plausible rather than speculative.
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Figure 3. Diagram of auditory localization experiment conducted in situ within the ancient architecture at the UNESCO World Heritage archaeological site at Chavín de Huántar, Perú. Shown are sound stimulus (six loudspeakers; “SOURCE”) and par- ticipant (eight human figures; “POS”) loca- tions within the interior space known as the “Doble Ménsula (double-corbel) Gallery,” drawn to scale as shown by 1.68-meter hu- man figures. Directionality of calibrated 4– inch single-driver loudspeakers and partici- pant-facing directions as drawn. Illustration by José L. Cruzado Coronel (Kolar, 2013).
Archaeoacoustical Interpretation in Archaeological Research
Archaeoacoustics produces assessments of the dynamical potential of archaeological materials, to support broader ar- chaeological interpretation. The fieldwork and conservation program led by John Rick at the 3,000-year-old UNESCO World Heritage site at Chavín de Huántar, Perú, has invit- ed and included archaeoacoustical collaboration since our project was formed at Stanford University in 2007. Figure 4 shows several archaeoacoustical techniques employed in research at this well-preserved ceremonial complex that oc- cupies about 14 hectares. In this research, converging forms of material cultural evidence support understandings of ancient communication (Kolar, 2017), including data from acoustical measurements of both site-excavated conch shell horns (Cook et al., 2010) and the well-preserved stone-and- earthen-mortar architecture. At Chavín, the only sound- producing instruments, either represented graphically (see Figure 5) or site excavated (see Figure 1), are the “Chavín pututus,” marine shell horns made from the eastern Pacific giant conch Strombus Lobatus galeatus. Because no written texts are known from Chavín, we can only infer from mate- rial evidence, including extensive use-wear to the shells, that these instruments were performed at the site.
Pututus may have been performed in many places in and around the Chavín ceremonial complex during the 1st cen- tury BCE. Their performance physics in groups produces compelling effects for Chavín’s ritual context, especially