How does one characterize an artist such as Jorge Reyes? He improvises and has studied with jazz musician Herb Geller, yet he is not a jazz performer. His presentations are filled with dance-like movement, yet he is not specifically a dancer. He is dedicated to the exploration and presentation of the music of the pre-Columbian Western Hemisphere, yet he is not an archeologist.

Reyes delights in the ambiguity. Like most artists who work in the expanding outer limits of their fields, he prefers to allow the music to speak for itself. And his music was indeed articulate Wednesday night at the El Rey Theater, when the Mexican-born artist offered a one-man, one-performance opportunity to experience his remarkable music. The appearance was triggered by, and associated with, his contributions to the score of the Salvador Carrasco film “La Otra Conquista” (The Other Conquest), with projected scenes from the movie accompanying the performance. (The film opens Wednesday.)

Reyes was chosen by Carrasco to provide music associated with pre-Cortes Mexico, juxtaposed against Samuel Zyman’s orchestral score (along with excerpts from Bach and the voice of Placido Domingo)--the musical pairing dramatically symbolizing the film’s depiction of the deadly and tragic encounter between two vastly different cultures.

Interestingly, however, there was a similar sort of juxtaposition in Reyes’ own performance. He stood at mid-stage, surrounded by equipment and instruments, dressed in white and wearing boots trimmed with shells. From time to time he picked up a frame drum, blew on a long, didjeridoo-like instrument, or laid down rhythms on a collection of drums and shakers. In those moments, he was distinctly shaman-like, an image that could have dated back for centuries.

At other times, however, Reyes was equally contemporary, using sophisticated audio equipment to create overlapping musical loops. Using grunts, growls, humming and singing, adding bursts of rhythm--some of it from drums, some from pounding his chest--he built hypnotically repetitious layers of sound. The effect was trance-like, a startlingly effective use of technology to render deeply emotional reactions.