In January 2004 I was invited to participate in Sound Oasis—a Francisco Rivero-Lake project, curated by Andrew Caleya Chetty, Jose Wolffer, and Manuel Rocha—a group show of twelve sound artists to be presented in the outdoor plaza at the Palacio de Bellas Artes, which is an especially popular meeting place in Mexico City. Each artist was commissioned to prepare two hours of sound for a 3D multichannel installation of 36 loudspeakers distributed throughout the plaza. Shortly before going to Mexico for a site visit, I read an Internet news release describing a collaborative research agenda just beginning in the cave directly under the huge Pyramid of the Sun in the ancient city of Teotihuacan, initiated by the physicist Arturo Menchaca, director of the National Autonomous University’s Physics Institute, and the archaeologist Linda Manzanilla, Mexico’s leading expert on the city of Teotihuacan.

Sub-atomic particles created by cosmic rays from space are to be used to probe a giant Mexican pyramid and solve one of the world’s greatest archaeological mysteries. Investigators are installing detectors beneath the Pyramid of the Sun at Teotihuacan that look for muons—charged particles generated when the cosmic rays that continuously shower the Earth hit the atmosphere. Each meter-wide detector will act as an ”eye” looking upwards in search of muons.

Developing TEO! became a most unusual and thrilling experience. I was able to enter the Cave under the Pyramid of the Sun with the physicists and make recordings with very simple means, which I later digitally processed in the studio.

A thematic feature of the ancient city of Teotihuacan is the number four, known to be a constant presence in the city which is split into four residential zones. TEO!—composed in four parts—addresses this feature spatially in the aural architecture I designed for the sonic imaging in the plaza.

Parts 1, 2, and 3 of TEO! were composed from the remnants of the recordings I made in the cave under the Pyramid of the Sun. I often find myself working with sonic debris, leftover sounds. In Part 3 for example, I initially rejected the somewhat sad ancient bagpipe-like sounds I heard. Eventually, though, I felt there was a certain truth here trying to assert existence. So I went with them, enhancing animation and presence through digital processing techniques. I was thrilled to discover a tuning for them which corresponded to the Leonid meteor showers recorded by the European Space Center.

To create a circulating movement for the beginning of Part 4(A), I edited a short phrase from a banjo solo performed and processed electronically by the composer, Ralph “Woody” Sullender, whose works I admire. The banjo was chosen for its clarity in providing a distinct concentrated spatial presence, in contrast to Pts 1-3 and Pt 4(B) in which the sonic imaging is distributed spatially and geometrically throughout the plaza.

Special thanks to the UNAM particle physicists’ research team led by Dr. Arturo Menchaca-Rocha, director of the Physics Institute, National Autonomous University of Mexico, and colleagues, Dr. Ernesto Belmont and Dr. Arnulfo Martinez, United States Government, Cultural Section, American Embassy, Mexico City.