In the process of its own maturity, musicals not only inherit the essence of opera but also absorb a variety of artistic expression factors. Since the first jazz musical "Watch Your Step" was staged in 1914, "jazz" has become the "musical saying" of musicals and the "American style imprint" of American musicals. From then on, the two became An indissoluble bond. In the 1930s, "Porgy and Bess" created by Gerst Wen in 1935 was a jazz musical. For example, the famous arias "Summertime" and "my man's gone now" in the play are all filled with rich black blues melodies. and songs with unique jazz rhythms; there are also arias with jazz music elements such as "can't help loving dat man" in "Show Boat" performed in 1927, but these early musicals with jazz music elements There are also characteristics of the times when singing. They mostly use pure bel canto singing method, with strong breathing support, focusing on the sound of the head cavity, high singing skills, and the more popular singing method of jazz has not yet been adopted. As musicals become more popular and entertaining, the jazz singing style in musicals gradually moves away from the aristocratic temperament of opera singing, and becomes more civilian and friendly, especially in works after the 1940s, such as "Kiss Me, Kate" why can't you behave", "somke gets in your eyes" in "Roberta" or the song "bye bye baby" and a large number of songs in "West Side Story" all use jazz singing style. The mastery of jazz singing style is first reflected in In terms of grasping the ontological characteristics of jazz music, in terms of the major scale of jazz, its third (Mi) and seventh (Si) notes are often lowered, and sometimes the fifth (Sol) note is also lowered by a half step. These falling tones are often supplemented by portamento and vibrato, which further enhances the melancholy and sad color of the song; syncopated rhythms and triplets are often used in the melody, resulting in an inversion of light and heavy sounds, especially continuous syncopation across bars often changes the original The rhythm shifts throughout the measure, creating an erratic sense of wandering. In terms of vocal characteristics, breath support and smooth "channels" are similar to Bel Canto singing. The voice is relaxed and elastic, but the chest and throat cavity are often used to sing, resulting in a hazy, dim, generous and deep voice color and magnetic feeling. Express the inner and delicate blues music style; when singing, it is close to the real voice, natural and friendly, and comes as naturally as speaking. The throat does not need to be too exaggerated, but the contrast of the strength and weakness of the timbre needs to be paid attention to; in jazz singing When grasping the style, pay attention to the tendency to lower the pitch level, the sliding tone between notes, sonic vibrato - the characteristics we commonly call "vibrato" and the improvisational processing of the swaying feeling of syncopated rhythm. Jazz singing style is very important and was widely used in musicals in the 1940s and 1950s and even later.