Rockport Chamber Music Festival’s 30th Anniversary Season brought violinist Stefan Jackiw and pianist Gilles Vonsattel to the Shalin Liu Performance Center on Saturday, June 11. (Jackiw pronounces his Ukranian surname “Ja-keev” rather than “Ya-keev.”) Both, now in their mid-twenties, were childhood friends and prodigies — in fact, Jackiw introduced their encore (the slow movement from Brahms’s third violin and piano sonata) by saying they had first performed it together in 1993, when he was eight and Vonsattel, twelve. Both went to Roxbury Latin School, and then on to private universities for  B.A. degrees:  Jackiw to Harvard, majoring first in psychology and then in music, and Vonsattel to Columbia, majoring in political science and economics. He also has a masters degree in music from Juilliard, and Jackiw, an artist’s diploma from New England Conservatory. Of course both had further intensive musical training here and elsewhere. These similarities and their long friendship may or may not explain the unusual musical partnership evident in their performance: not just soloist and accompanist, but true artistic interaction in expressing and shaping the music, while instinctively serving its aims. Both have formidable technique, but never use it for its own sake. Rarely have I heard artists so in tune with each other in so many ways. Vonsattel’s ringing sounds never overwhelmed Jackiw’s sensitive lyricism; in fact they often seemed to grow out of each other.

The program opened with Stravinsky’s six-movement Suite italienne (1932), one of many spinoffs from his immensely popular ballet music for Pulcinella (1919-20), including one for cello and piano of the same year, and itself a revision of an earlier version of 1926. During all that time Stravinsky understood that he was arranging melodies from manuscripts (later proven forgeries or music by other composers) of the 18th-century composer Giovanni Battista Pergolesi, some of which were dance movements (gavotte, minuet, tarantella). Although the original overture to Pulcinella (here, “Introduzione”) is marked Allegro moderato, it is usually played at a stately tempo, more Moderato than Allegro. The Jackiw-Vonstattel duo took this and the following movements at a much faster speed than the orchestral versions of the ballet. Thus the gavotte, for example, was more rapid than could be danced. Nevertheless the piece served as an introduction to the extremely romantic, yet delicate approach to performance taken particularly by Jackiw.

The apex of the concert for the audience was Brahms’s Violin Sonata no. 1, in G major, op. 78 (1878-79). Here the performers’ quiet intensity was most apparent, appropriate, and well received. This is a difficult piece for the pianist, with wide leaps that must be accomplished quickly without too much seeming effort, while the violinist enters and leaves with gentle wisps, expanding into much larger gestures, and long passages of double stops. Balance becomes crucial, and this they achieved with magical aplomb. Jackiw introduced the work, noting that the third movement makes reference to Brahms’s earlier “Regenlied” (Rain song). According to a 1995 article by Dillon Palmer, references to the song exist in all three movements, and Brahms indeed wanted the connections to be noticed.

After intermission we heard Luigi Dallapiccola’s Sonatina canonica su capricci di Niccol1ò Paganini (1942-43), for solo piano. In his introduction to the work Mr. Vonsattel described it as “deranged but affectionate,” a most apt description of this short, almost humorous piece, written in hiding, one could imagine as an obstinate response to Mussolini’s repressive Nazi policies during this time. (Dallapiccola’s wife was Jewish.) Indeed Dallapiccola wrote in 1953, “One day, in a mood of Galgenhumor (gallows humor), I wrote the Sonatina canonica … in a way as proof that … I was able to write in regular tonality, with a stated theme.” Each of the movements is based on one of Paganini’s violin caprices and requires difficult passage work. Vonsattel brought them off in just Dallapiccola’s spirit, with his characteristic clear pedaling and close dynamic control.

The final work was Richard Strauss’s only Violin and Piano Sonata, op. 18, written in 1887 at the end of his student days. It is a large (long) work, full of bombast, but also of surprisingly long, soft passages contrasting with the same dense complexity.  Nevertheless the performers triumphed with this seldom heard work whose exuberant “Finale” constitutes almost half the piece. The encore then further rewarded the audience, which honored the mood of each piece with a moment of respectful silence before applauding.

Mary Wallace Davidson has directed the music libraries at Radcliffe, Wellesley, Eastman School of Music, and Indiana University. She now lives in the Boston area.