AC4 was a Swedish hardcore punk band from Umeå, formed in 2008 by Dennis Lyxzén, Karl Backman, David Sandström, and Jens Nordén. The band's name derives from the regional code for Västerbotten province. AC4 gained initial attention with a live song posted on YouTube in 2008, which quickly garnered over 14,000 hits and was featured on Kerrang's playlist. Their debut album, AC4, was released in 2009 on Lyxzén's label Ny Våg. The band toured extensively across Europe and Australia and released the EPs Aniseed 001 and Umeå Hardcore EP. In 2013, AC4 released their second album, Burn the World, on Ny Våg Records, featuring notable songs like "Curva del Diablo" and "Burn the World". The band performed at various festivals, including Groezrock in spring 2013. AC4 disbanded shortly after, when Lyxzén decided to focus on other projects, but reunited at the end of the year for a farewell concert.
