Conversation so far:
What was Hardcore 81?
On April 22, 1981 the band released their second album Hardcore '81.
who was fired from the band?
Randy Rampage was fired from the band on January 1, 1982.
Who replaced him?
replaced by ex-Skulls drummer Dimwit on bass.
who left the band to work for Black Flag?
Chuck Biscuits left the band and joined Black Flag.
what type of production did the band have?
hard-rock oriented production.

Question: how did the band expound their sound?
Self-contained rewrite: How did the D.O.A band expound the hard Rock oriented sound?