Italian composer. Gastoldi was in the chapel of the Gonzaga family in Mantua, eventually as maestro di cappella (succeeding Giaches de Wert) from 1572 until 1608; then probably moved to Milan. Among his compositions are madrigals, a variety of sacred vocal music, and a small amount of instrumental music. Most prominent and influential, however, are his two sets of balletti, strophic vocal dance-songs with passages of nonsense syllables. These were often reprinted, widely known, and much imitated, especially outside Italy (e.g., by Thomas Morley).