Now his son is emerging as a major Wagnerian, leading acclaimed performances of the master’s works in Paris; at Bayreuth, the festival Wagner founded in Germany; and now at the Met, where his propulsive but intense “Ring” is earning strong reviews. Before he leaves his position in Paris, Mr. Jordan will conduct a new production of the “Ring” next year, staged by Calixto Bieito.

It was not always a given that this would be a podium dynasty. Mr. Jordan said that his father had initially been skeptical of his desire to conduct. “He didn’t really believe in that,” Mr. Jordan recalled. “So I had to prove it.”

He learned the craft the old-fashioned way: as a musical jack-of-all-trades at a small but busy German opera house, the theater in Ulm. “It was very bizarre: I started conducting, and my father was watching a little bit, and he became very supportive,” Mr. Jordan said. “All the doubts he had before turned around the other way. I got all the doubts; he was more encouraging.”

He got a grounding not only in opera but also in operettas and musicals; his first piece was “Funny Girl,” and he said he did “West Side Story” dozens of times. It was the approach favored by his father, who wanted him to learn the practical aspects of conducting by doing it, rather than going the route of conservatories, competitions and sporadic concerts. After several seasons in Ulm, Mr. Jordan became an assistant under Daniel Barenboim at the Berlin State Opera.

“The orchestra is the best teacher,” Mr. Jordan said. “You get an immediate response if it works or if it doesn’t work.”