Erlangen
Great place for metalheads. Not too stylish but cheap beer and Rock and Metal all night long!
Culture center which has Metal concerts quite often - check the program on their website for upcoming dates, tickets and stuff.
Small metal disco. A place for headbangers. Cheap beer, cheaper cola, water for free!! Openied in 1982, they play (loud!) all kinds of Metal and Rock including Classic Rock, Thrash, Death and Grind.