NEW YORK — One way to test a relationship is to travel together. There’s nothing like a change of environment and the odd sudden surprise for revealing the structural flaws in a partnership, or knitting it closer together. When the Royal Concertgebouw Orchestra and conductor Daniel Harding took the stage at Carnegie Hall on Thursday and Friday the maestro and the musicians, touring together, may been wondering: Is this working for me?

The Concertgebouw is one of the great orchestras in the world, and used to being wooed by stars. (As if to make the point, Friday’s program included Strauss’ “Ein Heldenleben,” which the composer dedicated to the players of this Dutch orchestra in 1898.)

Since its chief conductor, Daniele Gatti, was fired last summer over allegations of sexual impropriety (he denied the accusations), the orchestra has been searching for a new leader. When it tapped Harding, 43, an English conductor now mostly butterflying from one prestigious guest gig to another, to lead its American tour, many wondered if this was a first step toward something more lasting.

Last week’s performances showed that while the partnership is still far from symbiotic, it can, at its best, make thrilling music. The jitters were mostly felt during Thursday’s program, which included Schubert’s “Manfred” overture, Mozart’s Symphony No. 40 and Brahms’ Fourth. On Friday things came together gloriously in Beethoven’s “Emperor” Concerto with pianist Pierre-Laurent Aimard, “Heldenleben,” and a new work by Guillaume Connesson.

With its well-worn staples, Thursday’s program looked safe on paper. But the orchestra injected it with a dose of unpredictability by inviting members of the National Youth Orchestra of the United States of America to join its ranks.

This is part of an initiative the orchestra has developed at home and in European Union’ countries to give young musicians the experience of playing alongside first-rate professionals. It was a lovely gesture to extend on tour, even if it introduced the occasional unevenness into the Schumann.

The shakiness of the Mozart was harder to explain. The pops of dynamic contrast in the first movement came across as shrill rather than exuberant and the long arc of the andante’s melody seemed pieced together out of Lego blocks with the seams all too visible.

But Harding led an exciting reading of Brahms’ Symphony No. 4. The opening movement grows out of small motifs, in a way that can sound labored. Harding’s opening gesture was so expansive that the first sigh in the strings appeared to complete, or perhaps answer, a thought.

This was the opening to a burnished performance built on long narrative arcs and juicy color. Brahms’ music proved a perfect vehicle for this orchestra with its plush strings, warm and rounded brass sound and, especially, its impressive horn section. The concluding passacaglia brilliantly tied together the moments of archaic severity and private expression, with a memorable flute solo of deep, increasingly desperate, sadness.

“Eirene” is a 10-minute orchestral meditation on the Greek goddess of peace by Connesson, a stylistically omnivorous composer with a knack for scintillating textures. With its impressionistic opening giving way to sweeping melodies, the work has an appealing throwback glamour with touches of Mahlerian Weltschmerz and just a hint of jazzy swing.

It was a peaceful opening to a concert centered around celebrations of the heroic, including — in Strauss’ tone poem — a saber-rattling depiction of battle that the Concertgebouw players delivered with ferocious energy. But Harding and Aimard, the splendid soloist in the Beethoven concerto, also showed that a certain amount of restraint can lend deeper dignity to valor.

Their tempo in the first movement of the Emperor Concerto was sufficiently held back to lend the music a processional majesty. Dynamics were carefully balanced, with a glassy delicacy to the music-box passages and an almost tropical richness to the jubilant fanfares.

There was more dazzle to come in the Strauss, and plenty of moments in which individual players and sections took the spotlight. One of the orchestra’s concertmasters, Liviu Prunaru, showed off a magnificently full-bodied sound in his solos. Harding conducted elegantly, with intelligence and purpose.

Even so, I couldn’t help noticing that the musicians’ eyes were often elsewhere. String players often glance at each other, or keep their eyes focused on the concertmaster’s bow. Part of what makes this orchestra play so well is that its members approach the music like chamber musicians, which means that much of the time they don’t look at the conductor at all.

This article originally appeared in The New York Times.