Madrid night life

Hola ! Hello :)

I will be visiting Madrid this saturday and stay there till wednesday . and I am looking for a bar or night club (not like discos but where you can get drinks and talk etc ) a little bit off the beaten track I mean not the touristic bars but where locals do hang out.
So ı would appreciate if you can give some hints and tips.

I am big fan of Spain so I am sure Madrid will testify my good feelings.
thnx
xxx