Many of his songs are standard repertoire for vocalists and jazz musicians. The band consists of 6 women vocalists and instrumentalists. The Big Moon as backing vocalists and instrumentalists. The latter featured a number of guest vocalists and musicians. The album also featured some soulful female backing vocalists. She is one of the primary vocalists and songwriters for the band Eisley. Pop singer Michael Jackson cited Whitman as one of his ten favorite vocalists. Some power trios feature two lead vocalists. This began a trend that would continue with several other major jazz vocalists. Countertenors are also widely employed within opera as solo vocalists. Microphones are needed to record the sounds of vocalists or acoustic instruments. In 1966, Rivers began to record ballads that featured background vocalists. It is a duet featuring Starship vocalists Grace Slick and Mickey Thomas. He became one of the first major classical vocalists to make numerous recordings. Their eighth album was the only one to showcase all three vocalists.