Ginastera composed brilliantly in most genres – concertos, songs, string quartets, piano sonatas, and a number of film scores – but is best known for his early ballets Panambí and Estancia and the operas Don Rodrigo, Bomarzo, and Beatrix Cenci. Argentine folk songs and dances inspired and informed much of his music, whether in direct reference or in stylistic allusion. Later in his career he began to incorporate 12-tone techniques and avant-garde procedures into his music, ultimately reaching a synthesis of traditional and post-serial elements.

One of the first works of his 12-tone period was the Cantata para América Mágica, composed in 1960 and premiered at the Second InterAmerican Music Festival in Washington, D.C., in 1961 (along with Ginastera’s Piano Concerto No. 1). This large work for dramatic soprano and percussion orchestra mixes folkloric elements (indigenous instruments and pre-Columbian-inspired poems by Mercedes de Toro, Ginastera’s first wife) with thematic and structural devices common to the Second Viennese school (particularly retrograde formations, in both individual rows and in large palindrome forms).

The six movements of the work trace a narrative arc from invocation and romance to battle, defeat, and apocalyptic prophecy. The hinge is the fourth movement, the purely instrumental “Interludio fantástico.” It is a fleet, shimmering toccata that gradually adds instruments (but within a constant pianissimo range) until reaching a climax on a tremolo, 12-note chord, and then it recedes in reverse order. The singer’s wide-ranging lines have much of the angularity associated with 12-tone music of the time, but also a suggestion of vernacular ornamentation as well as motivic indentification. Ginastera’s free use of serial methods includes ostinatos and arpeggios, often giving a feeling of a tonal center. His huge percussion battery, ranging from two grand pianos to a pair of rocks struck together, provides rich resources to support his dramatic concept.