What does your username mean?

[novasonic]

Mines a former Korean metal band. They had a rapper as a lead singer for their 1st and 2nd album. He suffered a heart attack and phased himself out pretty quickly. He only sang 3 or 4 songs on the 3rd album, and the 4th had a completely new singer who wasn't bad, but was by no means as epic as the first. They broke up shortly after the release of their 4th album in 2003.