Decades before the Cuban revolution, some decidedly revolutionary sounds had their birth in that country’s capital city on today’s date in 1930 during a concert of ultra-modern music presented by the Havana Philharmonic. The concert offered the premiere performance of a new Piano Concerto by the American composer Henry Cowell, who was also the soloist. Cowell’s concerto broke new ground—and perhaps a few piano strings—by employing what Cowell dubbed “tone clusters.” These dense dissonant chords were produced by pounding the keys of the piano with the fist, palms, or extended forearms. Cowell also took his new techniques to the Old World in the 1920s and 30s, performing concerts of his works in Europe. These attracted the attention of Bela Bartok, who asked Cowell’s permission to employ tone clusters in his own works, and Arnold Schoenberg, who invited Cowell to perform for his Berlin composition classes. Cowell’s oft-stated goal was to embrace what he described as “the whole world of music,” whether dissonant or consonant, radical or traditional, Western or non-Western. Perhaps that ideal was even more revolutionary than his Piano Concerto must have seemed back in 1930.