The Brentano String Quartet built the first half of its Saturday concert at the Rockport Chamber Music Festival out of madrigals. That sounds odd, because (typically of string quartet concerts) not a single word was sung. But it proved an ingenious way to illustrate two of the Brentanos’ strengths: a polished lyricism in their sound, and the intellectual acuity of their programming. Taken together, the arrangements of three madrigals by the Italian Renaissance composer Carlo Gesualdo and The Fifth Book by American composer Stephen Hartke arched across centuries as a grand suite of music for absent or imaginary texts.

They began with arrangements by the Brentano’s first violinist Mark Steinberg of three madrigals from Gesualdo’s fifth book. The first, Asciugate i begli occhi, was played, beautifully, in that austere, almost vibrato-less approach that we reflexively refer to as “period style” when undertaken on modern instruments. But things changed drastically about a minute into the second madrigal, O voi troppo felici. Suddenly the tone color shifted as the music took on darker, chromatic inflections. The quartet’s players dug their bows into the strings during an agitated episode. The third madrigal, Tu m’uccidi o crudele, was so laden with dissonance and quick registral displacement that you wondered how the singers of Gesulado’s own time would have reacted. At these moments of theatrical intensity, you hungered to know what texts Gesualdo was setting in the original; with nothing in the printed notes, imagination ran riot.

This sequence of quick text-governed mood changes is fundamental to the idea of the madrigal, Steinberg said from the stage when introducing Hartke’s piece, and it’s a reason that of Hartke’s five books of madrigals, only two are written for voices. The others, like the Fifth Book (premiered last year by the Brentano), are for strings, but have the same character of responding “in quite mercurial ways to the emotional unfolding of text,” as Hartke wrote in a brief note.

There was an additional layer of reference to the Fifth Book, Steinberg explained. Hartke wrote it shortly after he relocated from southern California to Oberlin, giving the composer a fresh appreciation for the changing of the seasons. Hartke sketches that progression over five movements in kaleidoscopic colors and dense textures, often setting one or two instruments off against the others in a way that undercuts the music’s affect. In the first movement fitful, scurrying lines and icy double-stops evoke winter, while in the second a series of tempestuous shifts—from hammered accents to swooning unison melodies to musical arguments lead nowhere—allude to the anything-goes spirit of spring. Knotty harmonies in shadows underneath the sweet, summery lyricism of the violin melodies of the central movement suggest that all is not so carefree in this carefree time of the year.

Insistent, perpetual-motion runs evoke a windswept autumn, before winter returns in the final movement—a deeply poignant stretch whose earthbound melodies, closely voiced chords, and passionate outbursts carry the intensity of Shostakovich. The music died away as the Cape Ann sky, visible through the back window of Shalin Liu, darkened. How audibly close Hartke’s music is to actual madrigals is debatable, but there is no mistaking the illustrative capacity and sheer emotional power of the Fifth Book, which the Brentano played with dazzling assurance.

In Beethoven’s “Razumovsky” Quartet in F Major, Op. 59 No. 1, the mood changes of madrigals gave way to the dramatic architecture of classical and romantic forms. Still, when the Brentano paused at significant moments or slowed the tempo to highlight some musical detail, could one call such incidents madrigalesque? Could Beethoven have been hearing some secret text in his head to which he was responding?

At all events, the quartet gave a forceful, extroverted performance that took flight immediately with the rising cello melody that opens the piece. Although the Brentano boasts a lovely, balanced sound, they were more than willing to modify it or even cast it aside for expressive purposes, as the heavy-footed dance episodes of the scherzo or the slashing chords of the slow movement evidenced. Only in the finale did the group seem to tire, showing minor lapses of intonation and rhythm. Otherwise, this was a performance of insight and sweeping execution. Special mention should be made of cellist Nina Lee, whose solos throughout this quartet—in which Beethoven often placed the cello at the forefront—sang as beautifully as I can ever remember hearing.

David Weininger writes the Classical Notes column for the Boston Globe, where he also contributes features and reviews. He’s also written for Gramophone, BBC Music Magazine, the Boston Phoenix, and the website of Boston NPR station WBUR.