 In 1965, he became a founding member of the "Blues Project", a popular New York City folk rock band, along with Al Kooper, Danny Kalb, Steve Katz and Roy Blumenfeld.Kulberg was the band's bass guitarist, also known for his electric flute virtuosity.He later was a member of "Seatrain" which he formed with Roy Blumenfeld after the breakup of Blues Project in early 1969.