The beginning of the "swing" sound is difficult to pinpoint, but a variety of development in jazz of the late 1920s led to this new form in New York, featuring written arrangements and led by musicians such as Don Redman, Duke ellington. Employment for these groups came from large ballrooms, where a large ensemble was appropriate and organized arrangements featuring both improvisation and ensemble playing were used. While "two-beat" styles remained popular, especially with the white dance bands, black and white audiences began to listen and dance to a new style of jazz that featured a more restrained,"flat-four" feel to the music. The development of this style had a profound effect on the drummer and the entire rhythm section, which by the early 1930s included plano, drums, string bass , and guitar.