original passage: The surviving Shakers sing songs drawn from both the earlier repertoire and the four part songbooks. They perform all of these unaccompanied, in single-line unison singing. The many recent, harmonized arrangements of older Shaker songs for choirs and instrumental groups mark a departure from traditional Shaker practice.
original sentence: They perform all of these unaccompanied, in single-line unison singing.
sentence2: If a surviving Shaker had wanted to try out for American Idol, and was already okay with singing alone, would he or she also feel at home auditioning in the early rounds, when the singer must perform a capella style without any musical backup?
sentence1: The surviving Shakers sing songs drawn from both the earlier repertoire and the four part songbooks. They themselves perform all of these in single-line unison singing, with a small instrumental orchestra, although some outside groups prefer to perform unaccompanied tribute versions of the songs. The many recent arrangements of older Shaker songs for choirs or for solely instrumental groups mark a departure from traditional Shaker practice.