Tambor, composed between September 1997 and February 1998, was commissioned by Mariss Jansons and the Pittsburgh Symphony Orchestra, who gave the work's premiere on May 7 of the latter year; the score is dedicated to Robert Moir, the Pittsburgh Symphony's artistic administrator. The title, Tambor, is the Spanish word for "drum." Tower is familiar with that language, having grown up in South America, where her father worked as a mining engineer, and possibly the prominence and versatility of percussion instruments in Latin American music were influential recollections in her creation of this work, in which she assigns a major role to that section of the orchestra. She has kindly provided the following note of her own:
"This 15·minute work features the percussion section, whose five members (the timpanist and four others) essentially have three functions inside the orchestra:
1. to 'eyeline,' or underscore the different timbres and rhythms of other parts of the orchestra;
2. to 'counterpoint' other parts of the orchestra.; and
3. to act as soloists in several minor and major cadenzas throughout the work.
What happened while I was writing this piece was that the strong role of the percussion began to influence the behavior of the rest of the orchestra to the point that the other instruments began to act more and more like a percussion section themselves. In other words, the main 'action' of the work becomes more concerned with rhythm and color than with motives or melodies (though these elements do make occasional appearances here and there)."