Ancient Americans 'converted buildings into giant sound amplifiers'

A new study has claimed that ancient Americans used to turn buildings into giant sound amplifiers and distorters to enthrall or disorient audiences.

Temples at the ancient Maya city of Palenque in central Mexico, for example, might have formed a kind of "unplugged" public-address system, projecting sound across great distances, according to a team led by archaeologist Francisca Zalaquett of the Universidad Nacional Autonoma de Mexico.

Mayans built several types of instruments including rattling gourds filled with seeds or stones, turtle shells played with deer antlers, as well as whistles, ocarinas, modified seashells, and other wind instruments, said Zalaquett.

Performers and priests may have stood atop these temples or in specialized projection rooms, which still exist, to broadcast songs and chants throughout the squares. The Maya are known to have to held public rites to commemorate enthronements, births of nobles, and war victories as well as to honour deities, Zalaquett said.

"We think there was an intentionality of the builders to use and modify its architecture for acoustic purposes," National Geographic News quoted him as saying.

Using modern sound-measuring instruments and a 3D computer model of the site, the team concluded that sounds made atop a Northern Group temple can be heard clearly for at least the length of a football field (about a hundred yards or metres).

The "amplifiers" would have been the buildings themselves, and their acoustics may have even been purposely enhanced by the strategic application of stucco coatings, Zalaquett's findings suggest.

Measurements at some of the buildings still bearing stucco suggest it may have changed the absorption and reflection of sounds.

Archaeologist Chris Scarre, said the idea of the Maya and other ancient cultures creating acoustic effects using architecture isn't surprising. After all, temples and plazas were often "stage sets" for vast ceremonies.

"In that kind of context, if you can create a mysterious sound that seems otherworldly, you've created something that is a very powerful and intriguing element in the ceremony," he said.

It's unknown whether the builders of Palenque and Chavín intentionally designed the sites with auditory effects in mind. But maybe it doesn't matter, Scarre said. Ancient peoples, he reasoned, didn't have to understand how an effect was created to exploit it.

"Perhaps they started building structures that were designed in traditional ways," he said, "and then accidentally produced these effects."