It makes sense that Rockport would think to bring these artists together: both Yang and the Jupiter are young, acclaimed, and winners of major competitions. Their separate performances on the first half, however, raised some doubts about how they would combine on the second.

At the start of the show, the Jupiter announced from the stage that they were substituting Mozart’s D Major Quartet, K. 575 for the scheduled opener, Josef Haydn’s String Quartet in G Minor, Op. 74, No. 3 “The Rider”. No explanation was given, but Daniel McDonough, the cellist, jested that Mozart and Haydn were musical equals, so replacing one with the other was more-or-less inconsequential.

The quartet they chose, however, is really one of the rare weak pieces from Mozart’s late work. Written for amateur performance by the King of Prussia, it doesn’t hold up to the earlier and more ambitious six quartets Mozart dedicated to Haydn. If they had instead chosen one of those, it would be harder to quibble with the substitution.

The Jupiter provided a clean, articulate, but seemingly timid performance. This is a piece that needs as much help as it can get from its interpreters, but the Jupiter didn’t manage to hold interest. The dynamics were flat and there was little richness or complexity in the tone, perhaps because of the treble attenuation in the hall. McDonough, however, shone in his handling of the prominent cello part.

When Yang took the stage, the concert moved into a completely different world. Don’t judge the title — Bartók’s Out of Doors, SZ. 81 is no tepid pastorale for piano: It has calculated bombast, color, and vibrancy. Yang gave a compelling performance that balanced pianistic power with a sensitivity to the different voices that emerge from layered textures. The opening movement, With Drums and Pipes, was appropriately crunchy with dense clusters in the lowest reaches of the Steinway. The centerpiece of the set, Musiques Nocturnes, was full of splashy washes of color and meditative modal tunes harmonized in shadowy parallels. Yang presented this refreshing and original repertoire with flair and conviction.

So how did a pianist this bold combine with the subdued Jupiter? It turned out that the Franck Quintet was a reasonable place for these artists to meet. It’s a lush and sturdily built piece that doesn’t require ideally matched collaborators to make its point. The strings—violinists Nelson Lee, Megan Freivogel, violist Liz Freivogel, and McDonough—gave solid and emphatic support for Yang’s expressive touches and occasional fireworks from the keyboard. Finally, toward the end of the first movement, it seemed like some cross-pollination took place as the quartet brought some welcome grit into their sound.

It was a good move to give the guest pianist a solo turn instead of the usual quartet practice of inviting her just for a quintet at the end. There’s even something to be said for pairing very different artists. This kind of mix-and-match programming should be a staple at Rockport since it is so much in keeping with the summer festival spirit of experimentation and collaboration.

Benjamin Pesetsky is a Cambridge-based composer who’s recently been in residence at the Banff Centre and the Hambidge Center. Before that he attended Bard College where he studied with Joan Tower and George Tsontakis and earned a B.M. in composition and a B.A. in philosophy.