He debuted with a rock band of his own called "Downtown" in 1991, with bassist Jung Han-jeong and drummer Lee Chang-hyun; and produced their album DOWNTOWN in 1993. In 1994, N.EX.T's lead singer and founder Shin Hae-chul met with him and invited him to join the band as a guitarist, and he was with them until they disbanded in early 1998. That year, 1998, he formed the metal band NovaSonic with two other N.EX.T members, Kim Seung-hwan and Lee Su-yong, joined by rapper Kim Jin-pyo; remaining with them until 2005. He rejoined N.EX.T, when they regrouped in 2005, and remained with them until 2012. Also, during N.EX.T's hiatus, he played in the rock band 2Cell; and performed on albums for all three bands. Kim remembers favorite performances with N.EX.T, rehearsing at the Royal Albert Hall, performing concerts in South Korea with the Royal Philharmonic Orchestra and recording their 1997 album Lazenca (A Space Rock Opera) with the London Symphony Orchestra. He performed with the band again on August 8, 2015, for their last appearance at the Pentaport Rock Festival, along with other band members Kim Young-seok and Lee Su-yong, and other musicians, for a special memorial stage for their leader Shin, who died on October 27, 2014