I don't know if you still check Ancestry, but I have a Harry Feinberg in my tree that was born c. 1878 in Chicago. Parents were Max Feinberg and Anna Bernstein (I think). He had a brother Abe Feinberg (my great great grandfather). I don't know any other information on that side of the Feinberg tree. I believe that Max and Anna were both born in Russia in the 1850s.