<Li> Problems listening to the files? See media help . </Li> <P> "Folk music revival" refers to either a period of renewed interest in traditional folk music, or to an event or period which transforms it; the latter usually includes a social activism component . A prominent example of the former is the British folk revival of approximately 1890--1920 . The most prominent and influential example of the latter (to the extent that it is usually called "the folk music revival") is the folk revival of the mid 20th century, centered in the English - speaking world which gave birth to contemporary folk music . See the "Contemporary folk music" article for a description of this revival . </P> <P> One earlier revival influenced western classical music . Such composers as Percy Grainger, Ralph Vaughan Williams and Béla Bartók, made field recordings or transcriptions of folk singers and musicians . </P> <P> In Spain, Isaac Albéniz (1860--1909) produced piano works reflect his Spanish heritage, including the Suite Iberia (1906--1909). Enrique Granados (1867--1918) composed zarzuela, Spanish light opera, and Danzas Españolas--Spanish Dances . Manuel de Falla (1876--1946) became interested in the cante jondo of Andalusian flamenco, the influence of which can be strongly felt in many of his works, which include Nights in the Gardens of Spain and Siete canciones populares españolas ("Seven Spanish Folksongs", for voice and piano). Composers such as Fernando Sor and Francisco Tarrega established the guitar as Spain's national instrument . Modern Spanish folk artists abound (Mil i Maria, Russian Red, et al .) modernizing while respecting the traditions of their forebears . </P>

Which of the following is not a characteristic feature of traditional eastern european folk music