Les McCann is an American singer-pianist who has been active in the music industry since the 1960s. He is known for his soulful jazz and R&B music, as well as his collaborations with other artists. McCann has released several albums throughout his career, including his most successful album, 'Swiss Movement, ' which was released in 1969. He has also performed at various festivals and concerts around the world. McCann is considered to be one of the most influential musicians of the 20th century.