The richness and diversity of wind instruments of the Aymaran culture in the music of Bolivian Altiplano region have always deeply impressed me. At 4,000 meters of altitude, where the oxygen is so rarefied, a simple emotion can be a true challenge. Estratos opens with an acoustic exploration of the microphysical characteristics of these instruments, the “deficiencies” of their complex spectral structure, their “thick” sound, the thickening or rarification of their harmonics. The composition’s title refers both to the stratosphere, one of the upper layers above Earth, and to the layers of Earth’s crust, which are particularly characteristic in the Andes near La Paz. The composition process of Estratos reflects a geological moment by coupling several polyphonic and structural layers, resembling a complex web of rhythmic patterns and beats, of which some are reminiscent of the sounds of the Brazilian rainforest, generated by frogs and other nocturnal animals. The structure, instrumentation, and juxtaposition of various rhythmic patterns are reminiscent of the move toward unity of two distinct entities, characteristic for the Aymaran culture. Moreover, Estratos expresses my admiration for the Orquesta Experimental de Instrumentos Nativos and the work of Cergio Prudencio, to whom the work is dedicated.

Tato Taborda