Last night Vikings sailed into Longy’s Pickman Hall: in its Celebrity Series of Boston debut, the Danish String Quartet conquered New World audiences with music by Abrahamsen, Mendelssohn, and Debussy.

All four members of the quartet (actually three Danes and a Norwegian cellist) are Vikingsian young, blond men, and three sport beards worthy of Boston Red Sox players during the World Series. The skinny ties and more casual dress mark them as new and hip, but there is nothing casual about their artistry. They describe themselves as “simply your friendly neighborhood string quartet with above-average amounts of beard.” If only we could all live in such a musical neighborhood! Frederik Øland and Rune Tonsgaard Sørensen alternate between first and second violins (Øland playing first on the Mendelssohn in this concert); Asbjørn Nørgaard plays viola, and the Norwegian Fredrik Schøyen Sjölin plays cello. The violinists and violist met as children at a summer music camp for amateur musicians, and continued their studies together at Copenhagen’s Royal Academy of Music. The Danish String Quartet debuted in 2002 at the Copenhagen Festival, and Sjölin joined them in 2008, forming the current line-up. Throughout this program they played with a tight ensemble and constant interaction among the players. Their readings of the Mendelssohn and Debussy quartets were subtle and smart, with judicious and well-considered musical decisions building into interpretations that were unique, fascinating, convincing. This is a mature quartet with a fabulous future before them.

The program began with Hans Abrahamsen, String Quartet No. 1, “Ten Preludes” (1973). A member of the Danish ny enkelhed, or “new simplicity” movement, which is a reaction to the Darmstadt School of serialism, Abrahamsen’s quartet is a series of ten self-contained movements exploring a variety of musical styles even as recurring musical cells unite this series of character-piece preludes into a unified string quartet. Although I am not well-versed in this composer’s idiom, I heard similarities to the music of Terry Riley and Philip Glass in the focus on subtle change, repetition, and sparse or open harmonies. At the same time the piece opens with a piercing ferocity that signals Abrahamsen’s broader, more polyglot musical language, one which included chorales and traditional dance elements. This work is a compendium of musical forms and expressions and ends in a playful scherzo that is more traditional than the beginning. Individual preludes played with the idea of deferred resolution, even as the whole clutch of preludes comprising this string quartet find a unity in shared and repeated musical gestures. This work was played with drama and flair and the sheer artistry of the performance was inescapable.

Mendelssohn’s String Quartet No. 2 in A Minor, op. 13 (1827), written in the wake of Beethoven’s opus 132 quartet, is an homage to and an extenuation of the explorations of form and harmony Beethoven undertook in his quartet. The similarities are more noticeable for the differences between these works. The Adagio opened with a tenderness, a gut-wrenching hesitancy making of this a poignant start and imbuing the ensuing Allegro vivace with a patina of sadness that was enhanced by a judicious use of portamenti. Even the exuberance of Mendelssohn’s music in this opening movement was tinged with melancholy. The second movement, Adagio non lento, began as a lullaby then turned to a delicate fugato, before growing jagged and edgy as it developed in intensity:  a fury raging to escape the bounds of civility, then surprisingly calming into a rounded and sweet hymn. The third movement, Intermezzo:  Allegretto con moto – Allegro di molto, was lighter in spirit:  a small child skipping through sun-dappled fields of hay on the last day of summer. Again, an ineluctable sense of poignancy. The playful scherzo here opened with a subdued pianissimo. A highly effective ritardando brought back the lilting a-theme before the concluding amalgamation of these two ideas. The concluding Presto, like the Beethoven model, opens with a violin cadenza which Øland played with passion and verve in a lushly overwrought moment of anguish; this was a palpable stylistic conversation between late Beethoven and Classical restraint. The movement continued with vigor and intensity but did not shout in the full-blown expansiveness of later nineteenth century forceful expression. The performance ended in a resolute silence which the enthralled audience held.

Following intermission, the quartet gave a fully inhabited reading of Claude Debussy, String Quartet in G Minor, op. 10 (1893), with marvelously sinuous interplay among voices producing a sea of vibrating colors and resonant modalities. If, as one early critic opined, this music is “orgies of modulation,” then please, by all means, give me more—so long as it is played with such astute artistry and keen passion as this.

The Danish String Quartet returned to the stage to offer their thanks for being included in the Celebrity Series of Boston season, and offered as an encore Rune Tonsgaard Sørensen’s arrangement of a traditional Danish folk tune from the western Danish island of Sønderho often performed at weddings. This second tune from the Sønderho bridal trilogy can be heard on a CD of Scandinavian folk music the Danish String Quartet will be releasing on their own label in Spring 2014.

Cashman Kerr Prince, trained in Classics and Comparative Literature, is now a Visiting Scholar in the Department of Classical Studies at Wellesley College.  He is also a cellist of some accomplishment, currently playing with the Brookline Symphony Orchestra.