Living in Barcelona's El Raval

Hi!

My wife and I are interested in renting a flat in El Raval...Carrer Santa Elena near the intersection of Sant Pau and Av. Paral-lel. We hear bad things about El Raval, however, we know that the entire El Raval neighborhood can't be bad. Does anyone know about which parts of El Raval are more notorious than others? Are there any relatively safe parts of El Raval? Also, when people refer to the south part of El Raval, are they talking about the area south of La Rambla near Drassanes Metro station? Thanks!