Operatic pop or popera is a subgenre of pop music that is performed in an operatic singing style or a song, theme or motif from classical music stylized as pop. According to music historians, operatic pop songs became most prevalent with the rise of Tin Pan Alley musicians during the early 1900s. One influence was the large influx of Italian immigrants to the United States who popularized singers such as Enrico Caruso and inspired the creation of "novelty songs" using Italian dialect. The songs often used operatic repertory "to make a satirical or topical point". Popularized by American Vaudeville, musical comedies, jazz and operettas, examples include Irving Berlin's That Opera Rag, Billy Murray's My Cousin Caruso and Louis Armstrong's riffs on Rigoletto and Pagliacci. The subgenre subsequently dwindled after the 1920s but revived during the rock music era with albums such as The Who's Tommy and Queen's A Night at The Opera.
In 1986, operatic tenor Luciano Pavarotti had a hit with the Lucio Dalla song "Caruso", which helped to spark a recent flourishing of operatic pop. Other singers, including Andrea Bocelli, Josh Groban, and Katherine Jenkins, also recorded the number. Bocelli, in particular, soon became a leading representative of the subgenre. In the 2000s, singers and singing groups devoted primarily to operatic pop built on this renewed success. Groups like Il Divo and Amici Forever have achieved popularity with the mix of "contemporary pop with operatic style" characteristic of operatic pop. The subgenre is often performed by classical crossover singers and acts, although that field is much broader in the types of music it encompasses. "Popera" performances, such as those by the Three Tenors, have reached larger audiences and brought in greater profits than typical for operatic music.
Crossover is a term applied to musical works or performers appearing on two or more of the record charts which track differing musical tastes, or genres. If the second chart combines genres, such as a "Hot 100" list, the work is not a crossover.
In some contexts the term "crossover" can have negative connotations associated with cultural appropriation, implying the dilution of a music's distinctive qualities to appeal to mass tastes. For example, in the early years of rock and roll, many songs originally recorded by African-American musicians were re-recorded by white artists such as Pat Boone in a more toned-down style, often with changed lyrics, that lacked the hard edge of the original versions. These covers were popular with a much broader audience.
In practice crossover frequently results from the appearance of the music in question in a film soundtrack. For instance, Sacred Harp music experienced a spurt of crossover popularity as a result of its appearance in the 2003 film Cold Mountain, and bluegrass music experienced a revival due to the reception of 2000's O Brother, Where Art Thou?. Even atonal music, which tends to be less popular among classical enthusiasts, has a kind of crossover niche, since it is widely used in film-making and television production scores "to depict an approaching menace", as noted by Charles Rosen.