An American bass player most notable as a member of Blues Project and Seatrain.

He was born in Buffalo, New York. In 1965, he became a founding member of the Blues Project, a popular New York 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 was later a member of Seatrain which he formed with Roy Blumenfeld after the breakup of Blues Project in early 1969. Peter Rowan and Richard Greene were among the renowned members of Seatrain.

For nearly 20 years, Kulberg worked in Fairfax, California as a musician and composer, collaborating with Chris Michie. He died of lymphoma in 2002.