Wunderlich came from a musical family. His mother was a violinist and his father was a choir-master. The family did not find it easy to make a living, especially after Fritz's father committed suicide when Fritz was five years old. As a young man Wunderlich worked in a bakery. People heard him singing while he worked, and he was persuaded to study music. He got a scholarship to study at the Freiburg College of Music where he studied French horn and singing.