Kim Hak-chul, better known by his stage name Kim Yeon-woo (Korean: 김연우; born July 22, 1971) is a South Korean male singer, vocal coach, and professor at Seoul Art College (ko:서울종합예술학교). Nicknamed God of Vocals, he is well known for his ballads, smooth singing voice, and ability to hit high notes without difficulty. Kim recorded a number of hit ballads with the South Korean band, Toy, in the mid-to-late 1990s, gathering a sizable cult following. In 2011, Kim achieved widespread fame and recognition in South Korea through his participation on I Am a Singer, along with numerous appearances on variety and entertainment shows.