Acoustical Insights and Solutions for Archaeological Mysteries at Chichen Itza

Recent findings at Chichen Itza, Mexico suggest that its ancient builders were skilled theatrical sound designers who engineered sound for mind manipulation. Sound effects discovered so far seem uniquely appropriate for each monument and may be intentional designs. At the pyramid of Kukulkan (PK), echoes of handclaps are transformed into chirps of the resplendent quetzal, a bird venerated by the Maya since ancient times as messenger of the gods. Identifying the serpent shadow with the male quetzal’s diving behavior in the cloud forest at spring equinox supports intentional design of the chirp and provides an otherwise missing argument for intentional design of the PK. Transformation of handclaps into quetzal chirps would seem unexpected, even magical to both ancient and modern listeners. Since the chirped echo sounds unlike its handclap stimulus, some listeners may believe their handclap’s echo is not an echo, but an answer by a sentient being. In ancient times, this would support belief in the magical powers of Maya priests. Priests may also have acted as oracles by terminating questions to the gods at the PK with a handclap, then interpreting the chirped echoes as answers brought by the quetzal messenger of the gods. The chirped echo was once dismissed by archaeologists as an artifact of reconstruction. But evidence supportive of intentional design will be shown. Chichen Itza’s Great Ballcourt (GBC) is located close to the pyramid of Kukulkan.  Findings there also suggest that sound was engineered for mind manipulation. But GBC sound effects are different and varied, suggesting that ancient designers had a broad repertoire of acoustic design tricks. Used skillfully, the whispering gallery (WG) can produce mind-bending sound effects supportive of ancient Maya mythology described in their best-known creation story, the Popol Vuh. GBC sound effects include hallucinatory disembodied voices, shouting crowds, the whooping of an invisible bird flying rapidly through the playing field, and, with middling success, growling jaguars and menacing rattlesnakes. These animals are also represented in GBC carvings and frescoes. Some sound effects may seem supernatural even to modern listeners. The WG can also be used for speech reinforcement by officials standing on either end temple to address listeners in the playing field. If the GBC acoustical design is intentional, the ancient Maya were amazingly skilled at producing theatrical sound effects. Many of the effects achieved would be challenging if not beyond the capabilities of contemporary theater designers.