To cap its brief season, the Portland Chamber Music Festival scaled up its forces on Sunday, after treating its audience to transitional Berg and inspirational neo-tonalism with a heavy back-story.

In 1928 Alban Berg joined together in a suite, 7 of some 86 songs he wrote between 1900 and 1908, mostly (as all of this set were) while under the tutelage of Arnold Schoenberg. The texts ranged from Romantics like Nikolaus Lenau and Theodor Storm to his own contemporaries Rilke and Paul Hohenberg. Most take scenes of nature and interact them with human activity, and the suite is arranged so that the human component is most intense in the two middle ones, creating a kind of arch structure. It’s a bit harder to ascertain a distinct pattern in Berg’s settings, though both the first and last songs, Nacht by F. M. Hauptmann and Sommertage by Hohenberg, evoke their diametrically opposed scenes in whole-tone-inflected exoticism of a Straussian cast, while more straightforward settings hinting at Schumann and Schubert, in slots 2 and 5, are not thus symmetrically placed. The most harmonically daring is the erotically tinged no. 6, Otto Erich Hartleben’s Im Arm der Liebe schliefen wir selig ein, with a powerful conclusion on “Dreams of ecstasy, heavy with yearning.”

As performed by soprano Tony Arnold and pianist Diane Walsh, this little suite displayed fleeting wisps of dreamy haze with a firm, even sometimes steely, core. Arnold’s sure intonation, long-breathed lines and dynamic control brought color and variety to these mostly uniform, moderate-tempo songs; she generally maked her emotive points with subtle inflections. Walsh maintained a perfect counterpoise, becoming flashier only in the quite complex misterio introduction to Rilke’s Traumgekrönt.

One of the more popular recent works of chamber music (by which we mean a piece that has been performed and recorded by several discrete ensembles, to general acclaim) is David Bruce’s Gumboots for clarinet and string quartet (2008). It was performed in Boston this season; see review here. Bruce, 47, is a native of Connecticut but spends most of his time in the UK (one review of his music in a British publication refers to him as a British composer). Commissioned by Carnegie Hall for Todd Palmer (who performed it on this occasion) and the St. Lawrence String Quartet, it is popular for a variety of reasons. Most obviously, it is in an idiom that is immediately accessible, even pop-inflected. Gumoots’s emotionally engaging back-story involves Bruce’s study of South African gumboot (Wellies, high rubber boots) dancing that began as a form of communication among black gold miners during the apartheid years, when they were chained together and forbidden to speak. And finally, the piece follows that most appealing of musical progressions, from grim despair and anger to joyous celebration (think Beethoven 5 or 9), as the dancing evolves from protest to celebration of the resilience of the human spirit. Bruce has not sought to replicate the music of gumboot dancing, though he may have incorporated some of its rhythmic patterns, both of stepping and slapping the boots. (PCMF cleverly preceded the performance with a video illustrating the real thing). In fact, the music of the first three movements strongly suggests central Europe, while the latter sections echoed Copland in his Latin American moods, or maybe a Coplandesque Carlos Chavez).

Palmer, along with violinists Harumi Rhodes and Jennifer Elowitch, violist Dov Scheindlin and cellist Susannah Chapman, gave commitment and spirit to the quintet’s six movements. Palmer seems to have altered the scoring somewhat by using the regular clarinet’s chalumeau register instead of a bass clarinet for the opening, darkly colored movement (“Angry, ‘with attitude’”). The execution evolved into firecracker mode fairly quickly, with some awesomely controlled upper-register playing and Rhapsody in Blue glissandi. The crack up-to-date string writing included the slapping rhythms well portrayed by snap-pizzicato in several movements. The sly ensemble writing places the clarinet’s accents frequently at odds with those of the strings. The third movement, Forgotten Boots, the only one not designated as a dance, is ironically the most insistently catchy and toe-tapping. The rousing finale brought the house to its feet (though only its hands were in evident movement).

For the festival’s grand finale, Artistic Director Elowitch staffed up with a full dozen. Violinists David McCarroll, Katherine Fong, Rhodes, Elowitch, Lydia Forbes and Tracey Jasas-Handel, violists Carol Rodland, Scheindlin and Kirsten Monke, cellists Peter Stumpf and Chapman, and bassist William Blossom) teamed-up for a chamber-scale rendition of Dvořák’s Serenade in E Major, op. 22, one of the composer’s few early works to hold the boards. Some commentators (including program annotator Willard Hertz) half-apologize for the music as “transitional” Dvořák, reflecting more the Austro-German esthetic than the Czech nationalism he came to display; but our ears heard much of the latter, though the composer never really gave up the formational architecture of the central European tradition. The other thing this Serenade has going for it, of course, is Dvořák’s unstoppable fount of melody, whose primacy is abetted by the absence of any complex formal structure in the serenade’s five movements.

Channeling A Far Cry, the ensemble forwent a conductor, and proved that with performers this talented and artistically sympathetic, none was needed. They paradoxically achieved a full string sound while maintaining the individuality of line that bespeaks chamber music. Their gracious elegance came with a touch of peasant charm, notably in the second-movement waltz that represented a unique take on that Viennese form, reminding us in spirit of Virgil Thomson’s homey ones. The duple-meter scherzo deployed rubato with skill, while the Larghetto, as lovely as any of Tchaikovsky’s, conjured “a pause in the day’s occupations.” The finale, punchy without losing decorum, revealed some excellent dynamic phrasing. All in all, a great way to top off the year for PCMF.

Vance R. Koven studied music at Queens College and New England Conservatory, and law at Harvard. A composer and practicing attorney, he was for many years the chairman of Dinosaur Annex Music Ensemble.