Yannick Nézet-Séguin is about to open two of his most sprawling projects of the season, in separate cities, within two days of each other. On Tuesday, he conducts La Traviata in his first new production at the Metropolitan Opera since officially becoming music director this year. On Thursday, it's the Philadelphia Orchestra in Handel's Messiah at the Kimmel Center.

"They're pieces that I know inside and out … but we're trying to open up the music and take more time to reconsider every detail," he said last week.

He also dropped a mini-bombshell: New Met operas in the works by Kevin Puts and Mason Bates — the former starring Renée Fleming and the latter based on the acclaimed novel The Amazing Adventures of Kavalier & Clay — will first be heard in concert performances by the Philadelphia Orchestra. But that's in future seasons.

More immediately, the new La Traviata, directed by Broadway veteran Michael Mayer, promises to be lush and unashamedly beautiful — and, for the next decade or so, will dictate how American operagoers experience the famous story of a beautiful but tubercular courtesan who risks everything for love. Though Met revivals can be resurrected in a matter of days, this required at least four rehearsal weeks of Nézet-Séguin's attention.

Handel's Messiah is often given only a single rehearsal — and is farmed out to a guest conductor. But with his particular love for choral music, Nézet-Séguin has claimed the Christmas perennial for himself  —  it has more moving parts than some Mahler symphonies — and has assembled the kind of soloist lineup that reflects his industry-wide clout at the Met, plus how eagerly singers want to work with him. They are Carolyn Sampson, Christophe Dumaux, Jonas Hacker, and Philippe Sly.

Some of his days are a split shift divided between New York and Philadelphia. Nézet-Séguin's Orchestre Metropolitain in his hometown of Montreal isn't fading into the horizon, either, and is now recording for the Deutsche Grammophon label. (Which, by the way, continues raising the Philadelphia Orchestra's profile in its Rachmaninoff concerto recordings with pianist Daniil Trifonov.)

Amid all this, Nézet-Séguin never publicly complains about his workload. The pace, he said in our interview, is familiar.

Do you ever long for your less-pressured earlier life?

As long as I can remember, it has been like this. The school system of Quebec … has a two-year program that's specifically pre-college. I was around 16 or 17. I wanted to go into music but I also felt in need of studying something else at the same time — humanities, social sciences. Those classes were on one side of the city and my home was on the other. So practicing piano was, for me, midnight to 3 a.m., when my parents were asleep.

It didn't bother them and it was the only time I could practice. When I think about this and see myself today, I don't think there's so much of a change.

Even with pieces as different as La Traviata and Messiah competing for your brain space?

They bring me back to my early days at the Montreal Opera,when I was assistant to the conductor and chorus master. The very first opera I worked on was Traviata. And then the rest of my musical diet was sacred music [in church jobs].

This feels strange, but I've always behaved this way as a musician, to go and search for opposites in style. That's why I like to work on many things at the same time. They force me to identify their specific style.

When under pressure, is it easy to look for shortcuts?

I never think that way.

I used to be afraid that I was going to fall into a routine and was extra-animated. You may have noticed that I'm becoming less animated physically when I conduct. Having busy days, double-headers … they teach you to do this.

It's not that I want to save my energy but to channel it in a better way. It's about being so in the moment and so focused — and trusting not just myself but the ensemble that I lead.

In Philadelphia, I know they will know what I want. David Kim [the concertmaster] has been telling me this. He says, 'We know you so well and you're giving us so much that we can carry you.'

What have recent days looked like?

I try to have contrasting weeks. When you have a week of staging rehearsal with Traviata, I'm not driving the rehearsal. That's very different than having full days of double rehearsal in Philadelphia. It allows me to have balance. Repertoire between the two positions and two cities … will have different energies.

You’ve talked about future collaborations between the Philadelphia Orchestra and the Metropolitan Opera with future operas by Kevin Puts and Mason Bates. What will that look like?

I want to be shaping these works before a note is written, before the libretto is written. We will be workshopping these pieces in collaboration with the Curtis Institute. The Philadelphia Orchestra will premiere the scores in a concert presentation prior to the full production at the Met.

This will enable both cities to be part of the creative process. And the composers will be able to plant roots in many places.

Your main European commitment this spring is the Berlin Philharmonic. But this time, you’re not merely conducting a week’s worth of concerts in Berlin, but a four-city tour of Europe.

That's a good way of spending my European time this season. Now that I'm mostly in North America, every visit to Europe must be special in one way or another … but I already feel the benefits of not having jet lag all of the time.

You also have two Midwest dates with Joyce DiDonato this month in which she sings Schubert’s monumental Die Winterreise — which is typically sung by men. There’s a huge amount of interest in this. When is phase two?  

Realistically with her schedule and mine, it's a good idea to do it in phases. The next one will be in about a year.

But I take full blame and credit for leading her to this. I knew it would be so wild, so out of the box.

With so much moving around, have you and your partner, Pierre Tourville, had to redefine a sense of home?

In each place — Philadelphia, Montreal, New York — we have our habits, our routines, our coffee place, our bakery, our sushi place … to find a certain routine in a life where there's no such thing as routine.

When I have a week in Philadelphia, I have my own habits, what streets I like to walk on during Saturday afternoons. Even though the responsibilities are huge, it does feel like a more human life.

Do you have a New York apartment yet?

We're renting an apartment, and it takes me five minutes, door to door, to get to the Met. All of our furniture from Rotterdam is coming over on a ship.

The Philadelphia Orchestra performs Handel's "Messiah" Dec. 6, 8, and 9 at the Kimmel Center. Tickets: $49-163. Information: 215-893-1999 or philorch.org.

The Metropolitan Opera's "La Traviata" under Yannick Nézet-Séguin will be performed Dec. 4, 7, 11, 15, 18, 22, 26, and 29. Tickets start at $37. The HD simulcast in Philadelphia-area movie theaters is 12:55 p.m. Dec. 18. Information: 212-362-6000 or metopera.org.