One of the most fascinating aspects of chamber music is the ability of classical musicians to weave together the sound of “one person,” performing two or three parts. For Swiss chamber musicians Ambra and Fiona Albek share more in common than most members of a chamber group—they are identical twins..

Last Monday, the Albek twins played a concert in the Edward M. Pickman Concert Hall at the Longy School of Music. Violonist and violist Ambra and pianist Fiona—who hail from the Italian-speaking part of Switzerland—came to Boston as the last stop on their first tour of the United States. They performed pieces written by, among others, Béla Bartók, Joaquín Turina,

Richard Rodney Bennett, Leos Janacek, and Harvard’s own William P. Perry ’51., among others.

The twins opened their concert with selections from Turina’s “El poema de una Sanluqueña.” Before they began the piece, Ambra addressed the audience: “For this piece, we imagine ourselves in the south of Spain,” she said, with a lilting but easily understood Italian accent.

This sort of audience interaction characterized the entire night. Before each piece, Ambra and Fiona would give brief but enlightening details about the piece—why it was written, why they had chosen it, or how they were going to play it.

More striking than their interaction with the audience, though, was their interaction with each other. It is natural, of course, for skilled chamber musicians to have a strong connection with each other onstage. But the Albek twins have a connection built on decades, rather than months or years, of familiarity with each other. “We just notice that when we play together, we don’t need to say, ‘here we do a forte, here a piano’—we just feel these things at the same time,” said Ambra.

This connection was evident from the very beginning of Fiona and Ambra’s rendition of the Turina selection. The sisters played off each other’s energy, rising and falling perfectly together—not just in the sound they produced, but in the way they performed as well. When Ambra leaned into her violin more, Fiona put more weight into the piano. Each time Fiona smiled, it seemed Ambra would be smiling too.

The second piece the twins performed, entitled “The Nightingale in the Park,” was written especially for them by Perry. The  piece describes the world as viewed through a nightingale’s eyes in a park in Dublin. According to Perry, the piece was inspired in part by his background in scoring silent films. “I like to write programmatically,” Perry said. “Rather than simply say, ‘This piece is in sonata form, or rondo form, and here’s the second subject,’ and all of that—I like to visualize something happening.” The piece ends peacefully, with Ambra playing at the very highest end of the violin’s register as the bird flies to the top branch of a tree.

This piece stood in marked contrast to their third piece, “Sonata for Violin and Piano” by Czech composer Leos Janacek. Inspired by World War I, Janacek was a composer who was “desperate in his music,” Ambra said at the beginning of the performance. This desperation came through in Ambra’s insistent pizzicato and Fiona’s roiling arpeggios. “The piece is a little bit modern, but extreme,” said Fiona, emphasizing the last word. “We like that.”

In the Bennett piece, the waltz from “Murder on the Orient Express,” the ebullient twins even called for audience participation—they had a girl in the front row blow a train whistle whenever Ambra gestured toward her.

For the penultimate piece by Bartók, Ambra switched to viola, transitioning seamlessly without a loss of energy or technical proficiency.

The last piece they performed was, appropriately, both written and arranged by Italians. A reduction by Alessandro Lucchetti of Giacomo Puccini’s opera “Tosca,” the piece’s sweeping lyrical lines and dulcet harmonies captured an operatic spirit that closed the evening’s works with verve.

With a final encore of the Russian folk tune “Dark Eyes,” it was evident that the twins thoroughly enjoyed playing for American audiences. “We like the people [in America],” said Fiona. “They’re less complicated—this is a very big compliment! They’re more relaxed.”