The Huánuco Pampa acoustical field survey: an efficient, comparative archaeoacoustical method for studying sonic communication dynamics

Abstract

The 2015 acoustical field survey on and around the central plaza platform (“ushnu”) at the Inca administrative complex of Huánuco Pampa advances understanding of Inca communication dynamics and innovates archaeoacoustical methodologies. We detail here a new archaeoacoustics method that cross-compares a sequence of human-performed sound sources along with a standard electronic acoustical test signal across survey points. This efficient and rigorous archaeological experiment produced extensible data and observations regarding Inca-designed site sonics and multi-directional communication dynamics. Our experiment design combines ecologically valid acoustical measurements with subjective researcher-observer data to chart sound transmission and reception of different classes of sound-producers, enabling the identification of environmental contingencies, and the estimation of site acoustical features. Calibrated, multiply repeated sonic test signals were measured from a strategically chosen set of geo-located and photo-documented source and receiver locations in absolute, relative, and subjective terms, simultaneously for each source-receiver pair. This method offers a systematic and comprehensive understanding of site-specific sonic dynamics via in-field observations and data recording, frequency-range comparison across test signals, attention to acoustical metrics and psychoacoustical precedents, and emphasis on practical repeatability for a range of archaeologically relevant sound sources. Our study posits the central platform at Huánuco Pampa as a strategic point for Inca elites to both observe and influence activities across the site, a finding extensible to other such platforms. The prominent architectural platform would serve as a tool for multi-directional communication, as well as to facilitate messaging about elite presence and imperial identity through the projection of sonic-visual displays. Beyond producing data about Huánuco Pampa and Inca architecture, our case-study implementation of this new method demonstrates an efficient and systematic approach to tracing the acoustical contingencies of architectural materials in archaeological contexts.[Figure not available: see fulltext.].